- coin problem
- cointegral
- cointegral object
- cointegration
- cointegration analysis
- cointersection
- coin tossing
- coin-tossing game
- coinverse
- coirreducible category
- coirreducible object
- coisometric operator
- coisometry
- coisotropic
- coisotropic reduction
- coisotropic subspace
- coisotropic variety
- cok (= cokernel)
- coker
- cokernel
- cokernel of a morphism
- cokernel of an operator
- cokernel pair
- cokernel-preserving functor
- col