Lean Dictionary

Your free guide to Lean, Six Sigma, TPM, Theory of Constraints, and Continuous Improvement terminology.

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Balanced Scorecard

The Balanced Scorecard is a strategic management framework that measures performance across four perspectives: financial, customer, process, and learning.

Basic Stability

Basic stability is the foundational level of process reliability required before implementing advanced lean tools like kanban or heijunka.

Batch Size

Batch size is the quantity of items processed together before moving to the next step - smaller batches enable faster flow.

Batch-and-Queue

Batch-and-queue is a traditional production method where items are processed in large batches with waiting time between process steps.

Benchmark

A benchmark is a standard of excellence or best practice used as a reference point for comparing and improving organizational performance.

Best Practice

A best practice is a method or technique that has consistently shown superior results and is used as a benchmark for others to adopt.

Black Belt

A Black Belt is a full-time Six Sigma practitioner who leads complex improvement projects and mentors Green Belts.

Bottleneck Analysis

Bottleneck analysis identifies the constraint limiting system throughput, focusing improvement where it matters most.

Breakdown Maintenance

Breakdown maintenance is reactive repair performed only after equipment fails, addressing problems after they cause production stoppage.

Brownfield

Brownfield refers to implementing lean in an existing operation with established processes, equipment, culture, and constraints.

Buffer Management

Buffer management monitors the consumption of time or inventory buffers to identify problems early and prioritize improvement efforts.

Buffer Stock

Buffer stock is inventory held to protect against variability in production or demand, distinct from safety stock for supply variation.

Build-to-Order

Build-to-order is a production strategy where products are manufactured only after receiving a customer order, minimizing finished goods inventory.

C

Capacity Constrained Resource

A Capacity Constrained Resource (CCR) is a resource with capacity close to demand that could become the system constraint with small changes.

Catchball

Catchball is the back-and-forth dialogue process for aligning goals and plans between organizational levels in hoshin kanri.

Cellular Manufacturing

Cellular manufacturing organizes equipment and people into cells that produce complete products or components with minimal handling.

Chaku-Chaku

着々 (chaku-chaku)

Chaku-chaku is a production method where an operator loads machines in sequence while each machine automatically unloads and cycles.

Champion

A Champion is a senior leader who sponsors Six Sigma projects, removes organizational barriers, and ensures resources and support for project success.

Change Agent

A change agent is a person responsible for driving organizational transformation, helping others adopt new methods and ways of thinking.

Change Management

Change management is a structured approach to transitioning individuals, teams, and organizations from current state to desired future state.

Changeover

Changeover is the process of converting equipment from producing one product to another, including setup, adjustment, and trial runs.

Chief Engineer

主査 (shusa)

A chief engineer is the single person accountable for a product's success, integrating all functions and making final decisions throughout development.

Coaching Kata

The Coaching Kata is a structured pattern of questions that develops scientific thinking in others through guided practice.

Common Cause Variation

Common cause variation is the natural, inherent fluctuation in a process that occurs randomly and requires system-level changes to reduce.

Condition Monitoring

Condition monitoring tracks equipment health indicators in real-time to detect degradation and predict failures before they occur.

Constraint

A constraint is the single factor that most limits a system's ability to achieve its goal, determining overall throughput.

Constraint Management

Constraint management focuses improvement on the system bottleneck to maximize throughput with minimal investment.

Continuous Improvement

Continuous improvement is the ongoing effort to enhance products, services, or processes through incremental and breakthrough improvements.

Control Chart

A control chart is a statistical tool that monitors process variation over time, distinguishing between common cause and special cause variation.

Control Plan

A control plan documents the system for maintaining process improvements, specifying what to monitor, how to measure, and how to respond to deviations.

Corrective Action

Corrective action is a systematic process for eliminating the root cause of an identified problem to prevent recurrence.

Cost of Quality

Cost of Quality (COQ) measures the total cost of ensuring quality and the cost of failing to achieve it—prevention, appraisal, and failure costs.

Cpk

Cpk is a process capability index that measures how well a process performs relative to specification limits, accounting for both variation and centering.

Cross-Dock

Cross-docking is a logistics practice where incoming materials are transferred directly to outbound shipping with minimal or no storage.

Cross-Training

Cross-training develops employees in multiple skills or job functions to increase workforce flexibility and eliminate single points of failure.

CTQ

CTQ (Critical to Quality) characteristics are the measurable product or process attributes that directly impact customer satisfaction.

Current Reality Tree

The Current Reality Tree is a TOC logic diagram that maps cause-and-effect relationships to identify core problems underlying multiple symptoms.

Customer Focus

Customer focus is the practice of understanding and prioritizing customer needs as the basis for all operational decisions.

Cycle Time

Cycle time is the elapsed time to complete one unit of work from start to finish of a specific process step.

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FIFO

FIFO (First In, First Out) ensures items are processed or consumed in the order they arrived, preventing aging and maintaining flow.

Finished Goods

Finished goods are completed products ready for delivery to customers, representing the final inventory stage before sale.

First Pass Yield

First Pass Yield (FPY) is the percentage of units that complete a process step correctly the first time without rework, repair, or rejection.

Fishbone Diagram

A fishbone diagram organizes potential causes of a problem into categories, visually structured like fish bones around a spine.

Five Focusing Steps

The Five Focusing Steps are TOC's continuous improvement cycle: Identify the constraint, Exploit it, Subordinate to it, Elevate it, and Repeat.

Fixed-Position Stop System

A fixed-position stop system halts a moving production line at predetermined points, ensuring problems are addressed at specific locations.

Flow

Flow is the continuous movement of products, services, or information through value-creating steps without interruption, batching, or backflow.

Flow Production

Flow production is a manufacturing method where products move continuously through processes with minimal waiting or batch accumulation.

FMEA

FMEA (Failure Mode and Effects Analysis) is a systematic method for identifying potential failures, their causes, and effects to prioritize preventive actions.

Focused Improvement

Focused improvement (Kobetsu Kaizen) is the TPM pillar that uses cross-functional teams to eliminate specific equipment and process losses systematically.

Four Ms

The Four Ms (Man, Machine, Material, Method) are the fundamental inputs to any process, used for problem-solving and standardization.

Fulfillment Stream

A fulfillment stream is the complete flow of activities required to fulfill a customer order, from order receipt through delivery.

Future Reality Tree

The Future Reality Tree is a TOC logic tool that tests whether proposed solutions will achieve desired outcomes and identifies potential negative effects.

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Gage R&R

Gage R&R (Repeatability and Reproducibility) is a study that quantifies measurement system variation to ensure data quality for process improvement.

Gap Analysis

Gap analysis is a method for comparing current state to desired future state to identify the gaps that must be addressed to achieve goals.

Gemba

現場 (gemba)

Gemba means 'the real place' - the location where work happens and value is created, where leaders must go to understand actual conditions.

Gemba Walk

A gemba walk is a structured observation of the workplace where leaders go to see, ask questions, and understand actual conditions.

Genba Kanri

現場管理 (genba kanri)

Genba kanri is workplace management - the system of daily management practices that maintain and improve performance.

Genchi Genbutsu

現地現物 (genchi genbutsu)

Genchi Genbutsu means 'go and see for yourself' - the practice of direct observation at the source to understand the actual situation.

Go and See

Go and See is the practice of personally observing work at the actual location rather than relying on reports or secondhand information.

Green Belt

A Green Belt is a part-time Six Sigma practitioner who leads smaller improvement projects while maintaining regular job responsibilities.

Greenfield

Greenfield refers to designing new operations from scratch with lean principles built in from the start, without legacy constraints.

Group Leaders

Group leaders are front-line managers responsible for multiple teams, typically overseeing several team leaders and their work groups.

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Labor Linearity

Labor linearity is the ability to adjust labor proportionally to production volume, adding or removing workers as demand changes.

Lagging Indicator

A lagging indicator is a results metric that reports performance after the fact, confirming what has already occurred.

LAMDA Cycle

LAMDA (Look, Ask, Model, Discuss, Act) is a learning cycle used in lean product development for rapid knowledge building.

Lead Time

Lead time is the total elapsed time from when a request is made until it is fulfilled - the customer's experience of waiting.

Leader Standard Work

Leader standard work is a defined routine of activities that ensures leaders regularly perform essential management tasks like gemba walks and coaching.

Leading Indicator

A leading indicator is a predictive metric that signals future performance, enabling proactive intervention before results materialize.

Lean

Lean is a methodology for continuous improvement that maximizes customer value while eliminating waste, originating from the Toyota Production System.

Lean Leadership

Lean leadership is a management approach where leaders develop people, enable improvement, and create conditions for sustainable performance excellence.

Lean Promotion Office

A lean promotion office is an internal group responsible for coordinating, supporting, and sustaining lean transformation efforts across an organization.

Lean Thinking

Lean thinking is a management philosophy focused on maximizing customer value while minimizing waste through the five lean principles.

Leveling

Leveling is the practice of smoothing workload over time to eliminate peaks and valleys that cause waste and overburden.

Line Balancing

Line balancing distributes work elements across workstations to achieve even cycle times close to takt time.

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Master Black Belt

A Master Black Belt is an expert Six Sigma practitioner who trains and mentors Black Belts, develops methodology, and guides organizational deployment.

Material Flow

Material flow is the physical movement of materials, components, and products through production and logistics processes.

Material Handling

Material handling encompasses all activities involved in moving, storing, protecting, and controlling materials throughout production and distribution.

Maturity Model

A maturity model is a framework that describes progressive levels of capability development, from initial to optimized states.

Measurement System Analysis

Measurement System Analysis (MSA) is a collection of methods for evaluating whether a measurement system provides reliable, accurate data for decision-making.

Milk Run

A milk run is a fixed-route delivery system that picks up and delivers materials on a regular schedule, like traditional milk delivery.

Minor Stops

Minor stops are brief equipment interruptions lasting under 5 minutes that individually seem insignificant but collectively cause major productivity loss.

Mistake-Proofing

Mistake-proofing is designing processes and devices to prevent human errors or make them immediately detectable.

Monozukuri

ものづくり (monozukuri)

Monozukuri is the Japanese philosophy of making things with craftsmanship, pride, and continuous pursuit of excellence.

Monument

A monument is a large, inflexible piece of equipment that constrains material flow and production flexibility due to its size or capacity.

MTBF

MTBF (Mean Time Between Failures) measures average equipment reliability by calculating the average operating time between breakdowns.

MTTR

MTTR (Mean Time To Repair) measures average maintenance responsiveness by calculating the average time to restore failed equipment to operation.

Muda

無駄 (muda)

Muda refers to waste in any process - activities that consume resources without creating value for the customer.

Multimachine Handling

Multimachine handling is when one operator runs multiple machines of the same type, maximizing labor utilization during machine cycle times.

Multiprocess Handling

Multiprocess handling is when one operator runs different types of machines in sequence to complete a product through multiple operations.

Mura

(mura)

Mura refers to unevenness or inconsistency in processes that causes waste and makes work unpredictable.

Muri

無理 (muri)

Muri refers to overburden or unreasonable stress placed on people or equipment beyond their capacity.

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Paced Withdrawal

Paced withdrawal is the scheduled removal of finished goods at fixed intervals to create consistent demand signals upstream.

Pacemaker Process

The pacemaker process is the single point in a value stream that receives the production schedule and sets the pace for all upstream processes.

Pack-Out Quantity

Pack-out quantity is the standard number of units packaged together for shipping or movement between processes.

Pareto Chart

A Pareto chart combines bar and line graphs to show which factors contribute most to a problem, guiding improvement priorities.

PDCA

PDCA (Plan-Do-Check-Act) is a four-step continuous improvement cycle for testing changes and learning from results.

PDSA

PDSA (Plan-Do-Study-Act) is Deming's refined improvement cycle emphasizing studying results to understand why, not just what happened.

Perfection

Perfection in lean thinking is the theoretical state of zero waste, instant response, and perfect quality—the guiding star for continuous improvement.

PFEP (Plan For Every Part)

PFEP is a database documenting material flow specifications for every part number: storage locations, quantities, delivery methods, and container types.

Pitch

Pitch is the time increment for releasing work and moving materials, calculated as takt time multiplied by pack-out quantity.

Plan For Every Person

Plan For Every Person documents training requirements, current competencies, and development plans for every individual in an organization.

Planned Maintenance

Planned maintenance is scheduled, proactive equipment maintenance performed at predetermined intervals to prevent breakdowns and extend equipment life.

Point-of-Use Storage

Point-of-use storage positions materials at the exact location where they will be used, eliminating retrieval time and motion waste.

Poka-Yoke

ポカヨケ (poka-yoke)

Poka-yoke is mistake-proofing - designing processes and devices to prevent errors or make them immediately obvious.

Policy Deployment

Policy deployment is a strategic planning process that aligns organizational goals from top to bottom through cascading objectives and catchball dialogue.

Predictive Maintenance

Predictive maintenance uses condition monitoring and data analysis to predict equipment failures and schedule maintenance before breakdowns occur.

Preventive Action

Preventive action is a proactive process for eliminating potential causes of problems before they occur, based on risk analysis.

Preventive Maintenance

Preventive maintenance is scheduled, time-based or usage-based maintenance performed at regular intervals to prevent equipment failures.

Process Capability

Process capability measures how well a process meets specification requirements, comparing natural process variation to allowable tolerance.

Process Village

A process village is a traditional layout where similar machines or functions are grouped together, requiring products to travel between villages.

Product Family

A product family is a group of products that share similar processing steps and equipment, enabling flow cell design and value stream focus.

Product Family Matrix

A product family matrix is a tool that maps products against processing steps to identify product families with similar routings.

Production Analysis Board

A production analysis board displays real-time production status, targets, and problems to enable rapid response and continuous improvement.

Production Control

Production control is the function responsible for scheduling, sequencing, and coordinating production to meet customer requirements.

Project Charter

A project charter is a document that formally authorizes an improvement project, defining its scope, goals, team, and expected benefits.

Psychological Safety

Psychological safety is a shared belief that the team is safe for interpersonal risk-taking—speaking up, asking questions, and admitting mistakes.

Pull System

A pull system produces only when downstream processes signal demand, preventing overproduction and enabling flow.

Push System

A push system produces based on forecasts and schedules, pushing work downstream regardless of actual demand.

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Safety Stock

Safety stock is inventory held to protect against uncertainty in supply—delivery delays, quality rejections, or supplier disruptions.

Scatter Diagram

A scatter diagram plots two variables against each other to reveal relationships, correlations, or patterns between potential causes and effects.

Seiketsu (Standardize)

清潔 (seiketsu)

Seiketsu is the fourth of the 5S steps - creating standards and systems to maintain Sort, Set in Order, and Shine.

Seiri (Sort)

整理 (seiri)

Seiri is the first of the 5S steps - sorting through items to remove what is unnecessary from the workplace.

Seiso (Shine)

清掃 (seisō)

Seiso is the third of the 5S steps - cleaning the workplace thoroughly while inspecting for abnormalities.

Seiton (Set in Order)

整頓 (seiton)

Seiton is the second of the 5S steps - organizing remaining items so everything has a designated, labeled place.

Sensei

先生 (sensei)

Sensei is a teacher or master who guides lean transformation through hands-on coaching, challenging questions, and experiential learning.

Servant Leadership

Servant leadership is a philosophy where leaders prioritize serving their teams—enabling success by removing obstacles and providing support.

Set-Based Concurrent Engineering

Set-based concurrent engineering explores multiple design alternatives in parallel, gradually narrowing to an optimal solution based on learning.

Setup Reduction

Setup reduction focuses on minimizing the time and effort required to change from one product, batch, or configuration to another.

Shadow Board

A shadow board organizes tools with painted outlines showing each tool's designated location, making missing items immediately obvious.

Shipping Stock

Shipping stock is finished goods inventory staged and ready for imminent shipment, positioned near docks or loading areas.

Shitsuke (Sustain)

(shitsuke)

Shitsuke is the fifth of the 5S steps - maintaining discipline through training, audits, and continuous practice.

Shusa

主査 (shusa)

Shusa is the Toyota term for chief engineer—the heavyweight project leader accountable for a vehicle program's total success.

Sigma Level

Sigma level is a statistical measure of process capability that indicates how many standard deviations fit between the process mean and specification limits.

SIPOC

SIPOC is a high-level process map showing Suppliers, Inputs, Process, Outputs, and Customers to define project scope and stakeholders.

Six Big Losses

The six big losses are the primary categories of equipment productivity loss that TPM targets: breakdowns, setup, idling, speed loss, defects, and startup.

Six Sigma

Six Sigma is a data-driven methodology for eliminating defects and reducing variation in processes to achieve near-perfect quality.

Skill Matrix

A skill matrix is a visual tool showing team members' competency levels across required skills to identify gaps and guide development.

SMED

SMED (Single-Minute Exchange of Die) is a systematic approach to reducing changeover time to under ten minutes.

Spaghetti Diagram

A spaghetti diagram traces the path of movement through a workspace, revealing inefficient layouts and excessive travel.

Special Cause Variation

Special cause variation is unusual process fluctuation from specific, identifiable sources that can be investigated and eliminated.

Speed Loss

Speed loss is the gap between actual equipment running speed and its designed maximum rate, reducing output without causing stops.

Stability

Stability is the foundational state of predictable, reliable processes that enables continuous improvement and lean operations.

Standard Work

Standard work documents the best-known sequence, timing, and layout for performing work consistently and safely.

Standardization

Standardization is establishing and following the current best-known method for performing work consistently and predictably.

Statistical Process Control

Statistical Process Control (SPC) uses statistical methods to monitor and control processes, distinguishing normal variation from signals requiring action.

Strategy Deployment

Strategy deployment (hoshin kanri) is the process of translating strategic objectives into actionable plans throughout the organization.

Subordinate

Subordinate is the third of TOC's Five Focusing Steps—aligning all non-constraint resources to support and never impede constraint performance.

Suggestion System

A suggestion system is a structured process for collecting, evaluating, and implementing employee improvement ideas with recognition and feedback.

Supermarket

A supermarket is a controlled inventory location where products are stored for downstream pull, similar to retail supermarket shelves.

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Takt Board

A takt board displays takt time and actual cycle time, showing whether production is keeping pace with customer demand.

Takt Image

Takt image is a visual representation of what should happen at each takt time interval, making abnormalities immediately visible.

Takt Time

Takt time is the pace of production needed to match customer demand - the heartbeat that synchronizes all work.

Target Cost

Target cost is a price-driven costing approach where the allowable product cost is determined by market price minus required profit margin.

Team Leader

A team leader is a front-line lead who supports a small group of operators, responding to problems and maintaining standard work.

Theory of Constraints

Theory of Constraints (TOC) is a management philosophy that focuses improvement efforts on the system constraint that limits overall performance.

Thinking Processes

Thinking Processes are TOC logic tools for analyzing complex situations, identifying root causes, and developing effective solutions.

Throughput

Throughput is the rate at which a system produces finished goods or services - the output over a given time period.

Throughput Accounting

Throughput Accounting is a TOC decision-making method that evaluates choices based on their impact on Throughput, Inventory, and Operating Expense.

Tiered Accountability

Tiered accountability is a management system with cascading meetings that escalate unresolved issues from frontline to leadership on a defined schedule.

Time Study

Time study is the systematic measurement and analysis of work element times to establish standards and identify improvement opportunities.

Tollgate

A tollgate is a formal review checkpoint between DMAIC phases where leadership validates that required deliverables are complete before proceeding.

Total Productive Maintenance

Total Productive Maintenance (TPM) is a holistic approach to equipment maintenance that maximizes equipment effectiveness through operator involvement and proactive care.

Toyota Production System

The Toyota Production System (TPS) is Toyota's integrated manufacturing approach combining just-in-time, jidoka, and respect for people.

Toyota Way

The Toyota Way is Toyota's management philosophy built on two pillars: continuous improvement and respect for people.

Trade-Off Curves

Trade-off curves document the relationships between design parameters, showing how improving one attribute affects others.

Training Within Industry

Training Within Industry (TWI) is a structured methodology for developing supervisory skills in job instruction, job methods, and job relations.

True North

True North is the ideal state or perfect vision that guides continuous improvement direction, even if never fully achieved.

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Value

Value is any action or process that the customer is willing to pay for - the starting point for lean thinking.

Value Stream

A value stream is the complete sequence of activities required to transform raw materials or information into a product or service delivered to the customer.

Value Stream Mapping

Value Stream Mapping (VSM) is a visual tool for analyzing material and information flow from customer order to delivery.

Value-Stream Improvement

Value-stream improvement focuses on optimizing the entire flow from raw material to customer, not just individual process steps.

Value-Stream Manager

A value-stream manager has end-to-end accountability for a product family's flow, cutting across functional departments to optimize the whole.

Variance Analysis

Variance analysis is the process of comparing actual results to planned or expected values to understand the reasons for differences.

Vibration Analysis

Vibration analysis is a condition monitoring technique that detects equipment problems by analyzing mechanical vibration patterns and frequencies.

Visual Controls

Visual controls are mechanisms that make standards and abnormalities immediately visible without requiring inspection or data analysis.

Visual Management

Visual management uses visual signals and displays to make process status, performance, and abnormalities immediately obvious.

Voice of Customer

Voice of Customer (VOC) is the structured process of capturing customer needs, expectations, and preferences to guide product and process design.

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