impertinent vs sassy

impertinent and sassy both are adjectives.

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

As adjectives, impertinent and sassy are synonyms defined as:

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

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