Ck1
- 10146 Mukaitadashi
- 20043 Ellenmacarthur
- 3951 Zichichi
- 4198 Panthera
- 4836 Medon
- AIDC F-CK-1 Ching-kuo
- CK class
- Calvin Klein (company)
- Casein kinase 1
- Chang Kong CK-1
- Cicaré CK.1
- Crusader Kings (video game)
- F-16 Fighting Falcon variants
- Interim Biogeographic Regionalisation for Australia
- Keratin 1
- Type II keratin