Castor vs beaver

Castor and beaver both are nouns.

Word	Noun	Adjective	Verb	Adverb
Castor	Yes	No	No	No
beaver	Yes	No	Yes	No

Castor (noun)	beaver (noun)
type genus of the Castoridae: beavers	large semiaquatic rodent with webbed hind feet and a broad flat tail; construct complex dams and underwater lodges
a multiple star with 6 components; second brightest in Gemini; close to Pollux	a hat made with the fur of a beaver (or similar material)
	a movable piece of armor on a medieval helmet used to protect the lower face
	a man's hat with a tall crown; usually covered with silk or with beaver fur
	a full beard
	the soft brown fur of the beaver

Castor (verb)	beaver (verb)
	work hard on something