| communicating |
| commutable(adjective, interchangeable, proportionate, homologous, socialistic) |
| complementary(adjective, interchangeable, proportionate, homologous, socialistic) |
| completory(adjective, interchangeable, proportionate, homologous, socialistic) |
| concerted(adjective, combined, joined, dual) |
| concordant(adjective, interchangeable, jellied, proportionate, entire) |
| concrete |
| confederated |
| conformant(adjective, interchangeable, proportionate, homologous, socialistic) |
| conglomerated |
| conjunctive |
| consolidated(adjective, jellied, entire, combined, joined) |
| consonant(adjective, interchangeable, proportionate, homologous, socialistic) |
| cooperative(adjective, common, public, combined, shared) |
| coordinate(adjective, interchangeable, proportionate, homologous, socialistic) |
| copier(adjective, interchangeable, proportionate, homologous, socialistic) |
| corresponding(adjective, interchangeable, proportionate, homologous, socialistic) |
| coterminus(adjective, interchangeable, proportionate, homologous, socialistic) |
| curdled |
| dual(adjective, combined) |