nipping vs mordacious

nipping and mordacious both are adjectives.

Word	Noun	Adjective	Verb	Adverb
nipping	No	Yes	No	No
mordacious	No	Yes	No	No

As adjectives, nipping and mordacious are synonyms defined as:

Other synonyms of nipping include barbed, biting, pungent.

nipping (adjective)	mordacious (adjective)
pleasantly cold and invigorating	biting or given to biting
capable of wounding	capable of wounding