Synonyms for Butterfly (same or very similar meaning)
WordNet sense 1 (talk or behave amorously, without serious intentions):
coquette, dally, flirt, mash, philander, romance, coquet, chat upWordNet sense 2 (a swimming stroke in which the arms are thrown forward together out of the water while the feet kick up and down):
butterfly strokeFrom the ODE community, based on WordNetadd/edit