sidle up vs suck up

sidle up and suck up both are verbs.

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

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

sidle up and suck up: ingratiate oneself to; often with insincere behavior

Other synonyms of sidle up include cotton up, cozy up, play up, shine up.

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