Synonyms for Castor (same or very similar meaning)
WordNet sense 1 (a multiple star with 6 components; second brightest in Gemini; close to Pollux):
Alpha GeminorumWordNet sense 2 (a shaker with a perforated top for sprinkling powdered sugar):
casterWordNet sense 3 (a hat made with the fur of a beaver (or similar material)):
beaverWordNet sense 4 (type genus of the Castoridae: beavers):
genus CastorFrom the ODE community, based on WordNetadd/edit