3. chat up, flirt, dally, butterfly, coquet, coquette, romance, philander, mash -- (talk or behave amorously, without serious intentions; "The guys always try to chat up the new secretaries"; "My husband never flirts with other women")
4. dally, trifle, play -- (consider not very seriously; "He is trifling with her"; "She plays with the thought of moving to Tasmania")