- close pass
- close rafter
- close sand
- close supervision
- close-boarded
- close-coupled
- close-grained
- close-shut
- close-up
- closed
- closed aggregate
- closed anticline
- closed chain
- closed circuit
- closed circularity
- closed circulating
- closed clause
- closed competition
- closed conduit
- closed contact
- closed container
- closed coupling
- closed curve
- closed cycle
- closed diaphragm
- closed dragline
- closed fault
- closed fold
- closed loop
- closed mapping
- closed motor
- closed path
- closed polygon
- closed port
- closed process
- closed ring
- closed set
- closed shell
- closed spanner
- closed state
- closed steam
- closed stope
- closed system
- closed traverse
- closed vessel
- closed work
- closedown
- closely-packed
- closeness
- closer
- closet
- closet basin
- closet bowl
- closet horn
- closing
- closing cock
- closing contact
- closing error
- closing force
- closing head
- closing line
- closing machine
- closing point
- closing session
- closing switch
- closing time
- coboundary
- cochain
- cochannel interference
- cock
- cock key
- cock pit
- cock valve
- cocking
- cockle stair
- cockled surface
- cockles
- cockpit
- cockscomb
- coconnected
- coconut
- cocoon
- coction
- cocycle
- code
- code breaking
- code class
- code clerk
- code conversion
- code converter
- code current
- code editions
- code generation
- code key
- code letter
- code level
- code line
- code map
- code message
- code name