| C021 | CAD | Computer-Aided Design | Software-based tool for creating precise engineering drawings and models | Using AutoCAD to design a gearbox |
| C022 | CAE | Computer-Aided Engineering | Use of computer software to aid in engineering analysis tasks | Running FEA simulations in ANSYS |
| C023 | CAM | Computer-Aided Manufacturing | Use of software to control machine tools in manufacturing | Programming CNC machines |
| C024 | CAPEX | Capital Expenditure | Funds used by a company to acquire or upgrade physical assets | Buying new CNC lathes for a workshop |
| C025 | CATIA | Computer-Aided Three-Dimensional Interactive Application | A leading CAD/CAM/CAE software suite | Designing an aircraft fuselage |
| C026 | CBA | Cost-Benefit Analysis | Evaluation of financial benefits vs costs for a project | Analyzing ROI for new production line |
| C027 | CBT | Computer-Based Training | Training delivered through computers and digital means | Learning CNC programming via e-learning |
| C028 | CC | Cubic Capacity | Engine displacement measurement in cubic centimeters | A 150cc motorcycle engine |
| C029 | CCF | Cooling Capacity Factor | Ratio indicating efficiency of a cooling system | HVAC system rating |
| C030 | CCM | Cubic Centimeter | Volume measurement unit | Measuring cylinder displacement |
| C031 | CCP | Critical Control Point | Step in manufacturing where control is essential to prevent hazards | Heat treatment stage monitoring |
| C032 | CCR | Continuous Casting and Rolling | Metallurgical process for producing metal products | Continuous steel slab production |
| C033 | CCS | Carbon Capture and Storage | Technology to trap and store CO₂ emissions | Industrial smokestack carbon capture |
| C034 | CCT | Continuous Cooling Transformation | Diagram showing metal transformation during cooling | Heat treatment of steel |
| C035 | CCV | Crankcase Ventilation | System that removes harmful gases from engine crankcase | PCV valve in an automobile |
| C036 | CD | Coefficient of Drag | Aerodynamic resistance measure | Car wind tunnel testing |
| C037 | CDF | Cumulative Distribution Function | Statistical function for probability data | Failure probability analysis |
| C038 | CDI | Capacitor Discharge Ignition | Ignition system using capacitor discharge | Two-stroke motorcycle ignition system |
| C039 | CDR | Critical Design Review | Formal review during design phase of a project | Reviewing a new turbine blade design |
| C040 | CDS | Continuous Drive Shaft | A shaft transmitting rotational power | Vehicle driveshaft |
| C041 | CEC | Crankshaft End Clearance | Axial clearance in crankshaft mounting | Engine assembly inspection |
| C042 | CEI | Civil Engineering Institute | Organization related to civil engineering | CEI membership for structural engineers |
| C043 | CEM | Cement | Common construction material | Concrete manufacturing |
| C044 | CEO | Chief Executive Officer | Company’s highest-ranking executive | Head of an engineering firm |
| C045 | CER | Cost Estimating Relationship | Mathematical model to estimate cost | Predicting ship construction costs |
| C046 | CES | Controlled Environment System | System maintaining specific environment conditions | Cleanroom HVAC system |
| C047 | CFC | Chlorofluorocarbon | Compound once used in refrigeration | R-12 refrigerant |
| C048 | CFD | Computational Fluid Dynamics | Numerical analysis of fluid flows | Simulating airflow over a wing |
| C049 | CFG | Configuration | Arrangement of parts or system | CAD assembly layout |
| C050 | CFM | Cubic Feet per Minute | Unit of airflow rate | Air compressor capacity rating |
| C051 | CFPS | Certified Fire Protection Specialist | Professional fire safety credential | Designing sprinkler systems |
| C052 | CG | Center of Gravity | Point where object’s mass is balanced | Locating CG in aircraft |
| C053 | CGA | Compressed Gas Association | Sets standards for gas cylinders | Gas cylinder color coding |
| C054 | CH | Cylinder Head | Top part of engine containing valves | Diesel engine head assembly |
| C055 | CHB | Channel Bar | Steel bar with U-shaped section | Structural support member |
| C056 | CHG | Change | Alteration or modification | Engineering change order |
| C057 | CHP | Combined Heat and Power | System generating both electricity and heat | Industrial cogeneration plant |
| C058 | CHS | Circular Hollow Section | Steel tube with circular cross-section | Structural steel frame |
| C059 | CI | Cast Iron | Strong, brittle iron-carbon alloy | Engine block casting |
| C060 | CIA | Continuous Improvement Approach | Ongoing effort to enhance processes | Lean manufacturing practice |
| C061 | CID | Component Identification | Number or code for part tracking | Labeling machine components |
| C062 | CIM | Computer Integrated Manufacturing | Integrated computer systems in manufacturing | Smart factory automation |
| C063 | CIP | Cleaning In Place | Cleaning system without disassembly | Dairy plant pipe cleaning |
| C064 | CIR | Circular | Shape descriptor | Round cross-section shaft |
| C065 | CIS | Common Intake System | Engine air intake arrangement | Turbocharged engine intake |
| C066 | CJ | Control Joint | Groove in concrete to control cracking | Sidewalk expansion joint |
| C067 | CK | Check | Verification step | Quality control inspection |
| C068 | CKT | Circuit | Closed path for electrical flow | Electrical wiring diagram |
| C069 | CL | Center Line | Reference line in drawings | Machine alignment |
| C070 | CLA | Contract Labor Agreement | Employment agreement for contract workers | Hiring welders for a project |
| C071 | CLD | Cladding | Outer covering of a structure | Stainless steel cladding on vessel |
| C072 | CLE | Clearance | Space between parts for function | Bearing clearance measurement |
| C073 | CLF | Coefficient of Lift | Aerodynamic lift measure | Aircraft wing design |
| C074 | CLM | Clamping | Holding parts together | Milling fixture setup |
| C075 | CLS | Class | Category or grade | ASME pipe class |
| C076 | CLT | Cross Laminated Timber | Engineered wood product | Prefabricated timber building |
| C077 | CM | Centimeter | Unit of length | Measuring shaft diameter |
| C078 | CMA | Critical Machining Area | Area requiring precise machining | Bearing seat area |
| C079 | CMC | Ceramic Matrix Composite | High-strength composite material | Turbine blade manufacturing |
| C080 | CMD | Command | Instruction to a system | CNC G-code commands |
| C081 | CME | Continuing Mechanical Education | Ongoing learning for engineers | Attending ASME workshops |
| C082 | CMF | Cost Multiplication Factor | Used in cost estimation | Multiplying base cost in budgeting |
| C083 | CMM | Coordinate Measuring Machine | Precision measurement device | Inspecting engine block dimensions |
| C084 | CMP | Composite | Material made from two or more components | Carbon fiber-reinforced polymer |
| C085 | CMS | Condition Monitoring System | Tracks equipment health | Vibration monitoring in turbines |
| C086 | CMV | Commercial Motor Vehicle | Large transport truck | Freight logistics |
| C087 | CN | Control Number | Unique identifier for records | Drawing number in engineering |
| C088 | CNC | Computer Numerical Control | Automated machine tool control | CNC milling machine |
| C089 | CNG | Compressed Natural Gas | Alternative fuel | CNG-powered buses |
| C090 | CNR | Critical Nonconformance Report | Quality control record | Defective batch report |
| C091 | CNS | Central Nervous System | Control system of the body | Biomedical engineering |
| C092 | CNT | Count | Numerical quantity | Counting manufactured parts |
| C093 | CO | Carbon Monoxide | Toxic gas from incomplete combustion | CO sensors in boiler rooms |
| C094 | CO2 | Carbon Dioxide | Greenhouse gas | CO₂ fire extinguisher |
| C095 | COB | Close of Business | End of workday | Project deadline communication |
| C096 | COD | Chemical Oxygen Demand | Water quality measure | Wastewater plant testing |
| C097 | COE | Center of Excellence | Expert team in a domain | R&D in materials science |
| C098 | COF | Coefficient of Friction | Ratio of friction force to normal force | Brake pad friction testing |
| C099 | COL | Column | Vertical structural member | Steel building frame |
| C100 | COM | Communication | Exchange of information | SCADA system communication |
| C101 | CON | Connection | Joining two components | Welding pipeline sections |
| C102 | COP | Coefficient of Performance | Measure of efficiency | HVAC heat pump efficiency |
| C103 | COR | Correction | Adjusting an error | Re-machining a part |
| C104 | COS | Cost of Sales | Expense of goods sold | Fabrication shop accounting |
| C105 | COT | Coating | Protective surface layer | Galvanizing steel |
| C106 | CPU | Central Processing Unit | Computer’s main processor | PLC control unit |
| C107 | CP | Candle Power | Unit of luminous intensity | Testing headlamp brightness |
| C108 | CPA | Critical Path Analysis | Project scheduling method | Gantt chart planning |
| C109 | CPC | Cost Per Click | Advertising metric | Online marketing for engineering services |
| C110 | CPI | Continuous Process Improvement | Ongoing process optimization | Lean Six Sigma projects |
| C111 | CPL | Coupling | Device joining two shafts | Motor-pump coupling |
| C112 | CPM | Critical Path Method | Project management technique | Scheduling plant shutdown |
| C113 | CPN | Coupon | Test sample for inspection | Welding coupon |
| C114 | CPR | Critical Pressure Ratio | Pressure ratio where flow becomes choked | Nozzle design |
| C115 | CPT | Compression Test | Mechanical strength test | Testing spring stiffness |
| C116 | CR | Compression Ratio | Ratio of cylinder volume | Engine performance specification |
| C117 | CRA | Corrosion-Resistant Alloy | Alloy resistant to corrosion | Stainless steel piping |
| C118 | CRC | Cyclic Redundancy Check | Error-detection code | Data transmission integrity |
| C119 | CRF | Cross-Reference | Document linking reference | Technical manual indexing |
| C120 | CRH | Crushing | Breaking material into smaller pieces | Crusher machine operation |
| C121 | CRI | Color Rendering Index | Light source quality measure | LED lighting selection |
| C122 | CRP | Continuous Replenishment Program | Supply chain method | Automotive parts supply |
| C123 | CRT | Cathode Ray Tube | Display technology | Old oscilloscopes |
| C124 | CRV | Control Valve | Regulates fluid flow | Steam line pressure control |
| C125 | CS | Carbon Steel | Common engineering material | Pipe manufacturing |
| C126 | CSA | Canadian Standards Association | Standards body | CSA-certified electrical panels |
| C127 | CSC | Container Safety Convention | International safety standard | Shipping container compliance |
| C128 | CSD | Control System Design | Designing automated control systems | PLC-controlled process |
| C129 | CSE | Combustion Safety Engineering | Safety in combustion systems | Boiler safety |
| C130 | CSG | Cylindrical Surface Grinder | Machine for precision grinding | Shaft finishing |
| C131 | CSI | Construction Specifications Institute | Creates industry standards | Building specification manuals |
| C132 | CSL | Centerline Shift Limit | Allowable offset in assembly | Shaft alignment tolerance |
| C133 | CSM | Customer Service Management | Handling client relations | Engineering project support |
| C134 | CSO | Chief Security Officer | Oversees company security | Industrial plant security |
| C135 | CSP | Concentrated Solar Power | Solar energy technology | Solar thermal plant |
| C136 | CSR | Corporate Social Responsibility | Company’s environmental/social commitments | Green manufacturing initiatives |
| C137 | CSS | Cross-Sectional Shape | Shape of an object’s cross section | Structural design |
| C138 | CST | Centistoke | Viscosity unit | Oil viscosity testing |
| C139 | CSV | Comma-Separated Values | Data file format | Exporting measurement data |
| C140 | CT | Current Transformer | Measures electric current | Substation metering |
| C141 | CTA | Call to Action | Prompt to act | Website engineering service contact button |
| C142 | CTD | Cycle to Date | Accumulated production cycles | Maintenance logs |
| C143 | CTE | Coefficient of Thermal Expansion | Material expansion rate | Bimetallic strip design |
| C144 | CTG | Cutting Tool Geometry | Shape and angles of cutting tools | Lathe tool design |
| C145 | CTL | Control | Regulating process variables | PID control loop |
| C146 | CTO | Chief Technology Officer | Oversees technological developments | R&D in engineering firm |
| C147 | CTR | Center | Geometric midpoint | Shaft centering |
| C148 | CTS | Copper Tube Size | Plumbing standard | HVAC refrigerant piping |
| C149 | CTU | Cargo Transport Unit | Container for goods | Shipping container |
| C150 | CTV | Closed Circuit Television | Video monitoring | Factory security cameras |
| C151 | CU | Copper | Conductive metal | Electrical wiring |
| C152 | CUI | Corrosion Under Insulation | Hidden corrosion under insulation layers | Pipeline maintenance |
| C153 | CUP | Copper Units of Pressure | Ammunition pressure measure | Ballistics testing |
| C154 | CV | Control Volume | Region of space for fluid analysis | Fluid mechanics calculations |
| C155 | CVD | Chemical Vapor Deposition | Thin film coating process | Semiconductor manufacturing |
| C156 | CVI | Control Valve Index | Rating for valve performance | Valve selection in piping design |
| C157 | CVP | Constant Volume Process | Thermodynamic process | Internal combustion cycle analysis |
| C158 | CVR | Conversion Rate | Ratio of successful outcomes | Marketing for industrial services |
| C159 | CVS | Constant Volume Sampler | Device for measuring exhaust gases | Emissions testing |
| C160 | CW | Cooling Water | Water used to absorb heat | Power plant condenser cooling |
| C161 | CWP | Cold Working Pressure | Max pressure rating at low temp | Pressure vessel design |
| C162 | CWT | Center Winding Turret | Mechanism for winding rolls | Paper roll production |
| C163 | CY | Cylinder | Piston housing in an engine | Hydraulic cylinder |
| C164 | CYL | Cylindrical | Shape descriptor | Pipe geometry |
| C165 | CYS | Charpy V-notch Strength | Impact resistance measure | Steel toughness testing |
| C166 | CZ | Controlled Zone | Defined area in facility | Restricted lab access |
| C167 | CZN | Coarse Zinc | Zinc coating with rough texture | Galvanized steel sheet |
| C168 | CZO | Critical Zero Offset | Sensor calibration point | Strain gauge adjustment |
| C169 | CZS | Cold Zinc Spray | Zinc coating method | Corrosion protection |
| C170 | CZT | Cadmium Zinc Telluride | Semiconductor material | Radiation detectors |
| C171 | CZV | Critical Zero Velocity | Measurement state in navigation | Inertial navigation system |
| C172 | CZZ | Controlled Zero Zone | Precision machining reference | CNC tool calibration |
| C173 | CWA | Clean Water Act | U.S. environmental law | Industrial wastewater management |
| C174 | CWB | Canadian Welding Bureau | Welding certification body | CWB-certified welders |
| C175 | CWF | Cold Water Flow | Flow of cold water supply | Plumbing design |
| C176 | CWG | Cold Working Gauge | Tool for measuring deformation | Metal forming |
| C177 | CWH | Cold Water Head | Pressure head from cold water | Hydraulic system |
| C178 | CWI | Certified Welding Inspector | Professional welding certification | Pipeline welding inspection |
| C179 | CWL | Center Water Line | Reference line in piping | Marine engineering |
| C180 | CWM | Cold Water Meter | Device for measuring water volume | Municipal water supply |
| C181 | CWN | Cold Water Nozzle | Sprays cold water | Cooling tower system |
| C182 | CWO | Cold Water Outlet | Exit for cold water | Chiller system |
| C183 | CWP | Continuous Welded Pipe | Pipe manufactured without seams | Oil pipeline |
| C184 | CWR | Cold Water Return | Pipe returning cold water | HVAC chilled water system |
| C185 | CWS | Cold Water Supply | Source line for cold water | Building plumbing |
| C186 | CWT | Cold Water Tank | Tank storing cold water | Cooling system |
| C187 | CWV | Cold Water Valve | Regulates cold water flow | Plumbing fixture |
| C188 | CWW | Cold Water Well | Source for cold water | Industrial plant cooling |
| C189 | CWSR | Cold Work Stress Relief | Heat treatment to remove stresses | Sheet metal processing |
| C190 | CWSP | Cold Water Service Pipe | Pipe for cold water distribution | Residential water line |
| C191 | CWTS | Cold Water Transfer System | System for moving cold water | Industrial cooling loop |
| C192 | CWZ | Cold Water Zone | Zone in process using cold water | Food processing plant |
| C193 | CYA | Cover Your Assets | Risk management approach | Engineering contracts |
| C194 | CYB | Cybernetics | Study of systems and control | Robotics engineering |
| C195 | CYC | Cycle | Complete process loop | Engine four-stroke cycle |
| C196 | CYF | Cycle Factor | Multiplier for process cycles | Machine scheduling |
| C197 | CYL | Cylinder Lock | Locking mechanism type | Industrial equipment security |
| C198 | CYO | Carry Your Own | Self-contained equipment | Portable welding machine |
| C199 | CYP | Cylindrical Projection | Projection in drawings | Technical drafting |
| C200 | CYS | Cycles per Second | Frequency measure (Hertz) | AC power supply |