titty vs mammary gland

titty and mammary gland both are nouns.

Word	Noun	Adjective	Verb	Adverb
titty	Yes	No	No	No
mammary gland	Yes	No	No	No

As nouns, mammary gland is a hypernym of titty; that is, mammary gland is a word with a broader meaning than titty:

titty: either of two soft fleshy milk-secreting glandular organs on the chest of a woman
mammary gland: milk-secreting organ of female mammals

Other hypernyms of titty include mamma.

titty (noun)	mammary gland (noun)
either of two soft fleshy milk-secreting glandular organs on the chest of a woman	milk-secreting organ of female mammals