| English | Thesaurus |
| C⁴D | conductively connected CCD (Ladungstransfertechnik) |
| 4C-CD | Capital District Child Care Coordinating Council |
| CD4+ | CD4+ cell (T-клетка-хелпер у человека, являющегося мишенью для вируса СПИДа) |
| CD4 | CD4 (антигенный маркёр хелперных T-лимфоцитов) |
| CD4 | compact disc |
| CD-4 | compatible discrete 4-channel system |
| CD4 | helper-inducer T cells (Vosoni) |
| CD4 | HIV Helper Cell Count |
| CD4E | chain driven four-speed electronic transaxle |
| SE/4 | southeast quarter |
| SE/4 | south-east quarter |
| SE4All | Sustainable Energy for All (dragonfly_89) |
