blue tit vs tit

blue tit and tit both are nouns.

Word	Noun	Adjective	Verb	Adverb
blue tit	Yes	No	No	No
tit	Yes	No	No	No

As nouns, tit is a hypernym of blue tit; that is, tit is a word with a broader meaning than blue tit:

blue tit: widely distributed European titmouse with bright cobalt blue wings and tail and crown of the head
tit: small insectivorous birds

Other hypernyms of blue tit include titmouse.

blue tit (noun)	tit (noun)
widely distributed European titmouse with bright cobalt blue wings and tail and crown of the head	small insectivorous birds
	either of two soft fleshy milk-secreting glandular organs on the chest of a woman
	the small projection of a mammary gland