suck up vs truckle

suck up is not a noun while truckle is a noun.

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

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

Other synonyms of suck up include bootlick, fawn, kotow, kowtow, toady.

suck up (noun)	truckle (noun)
	a low bed to be slid under a higher bed

suck up (verb)	truckle (verb)
try to gain favor by cringing or flattering	try to gain favor by cringing or flattering
take in, also metaphorically	yield to out of weakness
ingratiate oneself to; often with insincere behavior