Verb has 2 senses

• chat up(v = verb.communication) butterfly, coquet, coquette, dally, flirt, mash, philander, romance - talk or behave amorously, without serious intentions; "My husband never flirts with other women"; "The guys always try to chat up the new secretaries"


Sample sentence:
Sam cannot %s Sue

• chat up(v = verb.communication) - talk to someone with the aim of persuading him;

Sample sentence:
Somebody ----s somebody