flycatcher vs peewee

flycatcher and peewee both are nouns.

Word	Noun	Adjective	Verb	Adverb
flycatcher	Yes	No	No	No
peewee	Yes	No	No	No

As nouns, peewee is a hyponym of flycatcher; that is, peewee is a word with a more specific, narrower meaning than flycatcher:

flycatcher: large American birds that characteristically catch insects on the wing
peewee: small olive-colored woodland flycatchers of eastern North America

flycatcher (noun)	peewee (noun)
any of a large group of small songbirds that feed on insects taken on the wing	small olive-colored woodland flycatchers of eastern North America
large American birds that characteristically catch insects on the wing	disparaging terms for small people