sidle up vs cotton up

sidle up and cotton up both are verbs.

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

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

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

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

sidle up (verb)	cotton up (verb)
ingratiate oneself to; often with insincere behavior	ingratiate oneself to; often with insincere behavior