- concave mirror
- concave tile
- concave weld
- concave-down
- concavo-concave
- concealed conduit
- concealed erosion
- concentrate
- concentrated brine
- concentrated force
- concentrated source
- concentrating table
- concentration cell
- compact sand
- compact-grained
- compacted soil
- compacting beam
- compacting factor
- compacting machine
- compaction device
- compaction roller
- compandor
- companion fault
- company
- comparator method
- comparer
- comparison test
- comparison value
- compartmented tray
- compass
- compass bearing
- compass compensating
- compass deviation
- compass error
- compass heading
- compass needle
- compass repeater
- compass roof
- compasses
- compatibility
- compatibility feature
- compatible computer
- compensate
- compensated
- compensated motor
- compensated voltmeter
- compensating error
- compensating instrument
- compensating network
- compensating rod
- compensating spring
- compensating winding
- compensation flow
- compensation network
- compensative
- compensator reservoir
- competent
- competition
- compilation
- compilation program
- compile duration
- compile time
- compiler
- compiling routine
- complement operation
- complementarity law
- complementary color
- complementary symmetry
- complete chilling
- complete cycle
- complete image
- complete integration
- complete limit
- complete refrigeration
- completely
- completeness check
- completion time
- complex algebra
- complex ore
- complex quantity
- complex stress
- complex variable
- complexity
- compliance
- component entry
- component part
- compose sequence
- composite circuit
- composite fault
- composite fold
- composite frame
- composite sampler
- composite syncline
- composites
- compost aeration
- composting
- compound angle
- compound bending
- compound circuit
- compound magnet