bird vs croup

bird and croup both are nouns.

Word	Noun	Adjective	Verb	Adverb
bird	Yes	No	Yes	No
croup	Yes	No	No	No

bird (noun)	croup (noun)
warm-blooded egg-laying vertebrates characterized by feathers and forelimbs modified as wings	the part of an animal that corresponds to the human buttocks
badminton equipment consisting of a ball of cork or rubber with a crown of feathers	a disease of infants and young children; harsh coughing and hoarseness and fever and difficult breathing
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)	croup (verb)
watch and study birds in their natural habitat