bird vs uropygial gland

bird and uropygial gland both are nouns.

Word	Noun	Adjective	Verb	Adverb
bird	Yes	No	Yes	No
uropygial gland	Yes	No	No	No

bird (noun)	uropygial gland (noun)
warm-blooded egg-laying vertebrates characterized by feathers and forelimbs modified as wings	oil-secreting gland situated at the base of the tail in most birds
badminton equipment consisting of a ball of cork or rubber with a crown of feathers
a cry or noise made to express displeasure or contempt
the flesh of a bird or fowl (wild or domestic) used as food
informal terms for a (young) woman

bird (verb)	uropygial gland (verb)
watch and study birds in their natural habitat