Source : WordNet®

chat up
     v 1: 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: {flirt}, {dally},
           {butterfly}, {coquet}, {coquette}, {romance}, {philander},
           {mash}]
     2: talk to someone with the aim of persuading him