too big for one's breeches vs snot-nosed

too big for one's breeches and snot-nosed both are adjectives.

Word	Noun	Adjective	Verb	Adverb
too big for one's breeches	No	Yes	No	No
snot-nosed	No	Yes	No	No

As adjectives, too big for one's breeches and snot-nosed are synonyms defined as:

too big for one's breeches and snot-nosed: (used colloquially) overly conceited or arrogant

Other synonyms of too big for one's breeches include bigheaded, persnickety, snooty, snotty, stuck-up, uppish.

too big for one's breeches (adjective)	snot-nosed (adjective)
(used colloquially) overly conceited or arrogant	dirty with nasal discharge
	(used colloquially) overly conceited or arrogant