bird vs young lady

bird and young lady both are nouns.

Word	Noun	Adjective	Verb	Adverb
bird	Yes	No	Yes	No
young lady	Yes	No	No	No

As nouns, young lady is a hypernym of bird; that is, young lady is a word with a broader meaning than bird:

Other hypernyms of bird include fille, girl, miss, missy, young woman.

bird (noun)	young lady (noun)
warm-blooded egg-laying vertebrates characterized by feathers and forelimbs modified as wings	a young female
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)	young lady (verb)
watch and study birds in their natural habitat