1. Zool. A genus of rodents, including the beaver. See Beaver.
2. Castoreum. See Castoreum.
3. A hat, esp. one made of beaver fur; a beaver.
I have always been known for the jaunty manner in which I wear my castor. --Sir W. Scott.
4. A heavy quality of broadcloth for overcoats.
Cast·or n. See Caster, a small wheel.
Cas·tor n. Astron. the northernmost of the two bright stars in the constellation Gemini, the other being Pollux.
Cas·tor, Cas·tor·ite n. Min. A variety of the mineral called petalite, from Elba.
n 1: a multiple star with 6 components; second brightest in
Gemini; close to Pollux [syn: Alpha Geminorum]
2: a shaker with a perforated top for sprinkling powdered sugar
3: a pivoting roller attached to the bottom of furniture or
trucks or portable machines to make them movable [syn: caster]
4: a hat made of beaver fur or similar material [syn: beaver]
5: type genus of the Castoridae: beavers [syn: genus Castor]