sassy vs impertinent

sassy and impertinent both are adjectives.

Word	Noun	Adjective	Verb	Adverb
sassy	No	Yes	No	No
impertinent	No	Yes	No	No

As adjectives, sassy and impertinent are synonyms defined as:

Other synonyms of sassy include fresh, impudent, overbold, saucy, smart, wise.

sassy (adjective)	impertinent (adjective)
improperly forward or bold	improperly forward or bold
	not pertinent to the matter under consideration
	characterized by a lightly pert and exuberant quality