fawn vs suck up

fawn is a noun but suck up is not a noun.

Word	Noun	Adjective	Verb	Adverb
fawn	Yes	No	Yes	No
suck up	No	No	Yes	No

As verbs, fawn and suck up are synonyms defined as:

Other synonyms of fawn include bootlick, kotow, kowtow, toady, truckle.

fawn (noun)	suck up (noun)
a young deer
a color or pigment varying around a light grey-brown color

fawn (verb)	suck up (verb)
have fawns	try to gain favor by cringing or flattering
try to gain favor by cringing or flattering	take in, also metaphorically
show submission or fear	ingratiate oneself to; often with insincere behavior