Castor
- Antonius Castor
- Belgian patrol vessel Castor
- Betty Castor
- Brian Castor
- Bruce Castor
- CASTOR (nuclear waste)
- CASTOR (spacecraft)
- CASTOR experiment
- Caistor
- Caistor St. Edmund
- Caster
- Caster (disambiguation)
- Caster angle
- Castor (1782 ship)
- Castor (1917 ship)
- Castor (band)
- Castor (cloth)
- Castor (footballer)
- Castor (framework)
- Castor (mountain)
- Castor (rocket stage)
- Castor (star)
- Castor (trucks)
- Castor Bay
- Castor Cantero
- Castor Cracking Group
- Castor Creek (Little River tributary)
- Castor High School
- Castor McCord
- Castor Oyl
- Castor River (Missouri)
- Castor River (Ontario)
- Castor Semenya
- Castor Temple
- Castor and Pollux
- Castor hat
- Castor of Apt
- Castor of Karden
- Castor of Rhodes
- Castor oil
- Castor oil plant
- Castor sugar
- Castor wax
- Castor, Alberta
- Castor, Cambridgeshire
- Castor, Louisiana
- Castore (brand)
- Castoreum
- Castro (disambiguation)
- Drusus the Younger
- Face/Off
- Gastor (disambiguation)
- George A. Castor
- Helen Castor
- Janus (moon)
- Jean-Victor Castor
- Jimmy Castor
- Kastor (disambiguation)
- Kathy Castor
- Orphan Black
- Persona 3
- Queue de Castor River
- Rivière aux Castors Noirs
- Shinjiro Aragaki
- Stacey Castor
- Steve Castor
- The Courts of the Morning
- The Harpy