philander vs chat up

philander and chat up both are verbs.

Word	Noun	Adjective	Verb	Adverb
philander	No	No	Yes	No
chat up	No	No	Yes	No

As verbs, philander and chat up are synonyms defined as:

philander and chat up: talk or behave amorously, without serious intentions

Other synonyms of philander include butterfly, coquet, coquette, dally, flirt, mash, romance.

philander (verb)	chat up (verb)
talk or behave amorously, without serious intentions	talk or behave amorously, without serious intentions
have amorous affairs; of men	talk to someone with the aim of persuading him