- (n.) Castoreum. See Castoreum.
- (n.) the northernmost of the two bright stars in the constellation Gemini, the other being Pollux.
- (n.) Alternative of Castorite.
- (n.) A genus of rodents, including the beaver. See Beaver.
- (n.) A hat, especially one made of beaver fur; a beaver.
- (n.) See Caster, a small wheel.
- (n.) A heavy quality of broadcloth for overcoats.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). castor. Retrieved September 20, 2026, from http://smartdefine.org/castor/definitions/1985170 |
| Chicago | Webster's. 2011. "castor" http://smartdefine.org/castor/definitions/1985170 (accessed September 20, 2026). |
| Harvard | Webster's 2011, castor, Smart Define, viewed 20 September, 2026, <http://smartdefine.org/castor/definitions/1985170>. |
| MLA | Webster's. "castor" 27 May 2011. Web. 20 September 2026. <http://smartdefine.org/castor/definitions/1985170> |