'chat up' definitions:

Definition of 'chat up'

From: WordNet
verb
Talk or behave amorously, without serious intentions; "The guys always try to chat up the new secretaries"; "My husband never flirts with other women" [syn: chat up, flirt, dally, butterfly, coquet, coquette, romance, philander, mash]
verb
Talk to someone with the aim of persuading him