drop the ball vs boob

drop the ball is not a noun while boob is a noun.

Word	Noun	Adjective	Verb	Adverb
drop the ball	No	No	Yes	No
boob	Yes	No	Yes	No

As verbs, drop the ball and boob are synonyms defined as:

drop the ball and boob: commit a faux pas or a fault or make a serious mistake

Other synonyms of drop the ball include blunder, goof, sin.

drop the ball (noun)	boob (noun)
	either of two soft fleshy milk-secreting glandular organs on the chest of a woman
	an ignorant or foolish person

drop the ball (verb)	boob (verb)
commit a faux pas or a fault or make a serious mistake	commit a faux pas or a fault or make a serious mistake