踏兩頭船 (daap6 loeng5 tau4 syun4) — literally: 'stepping on two ships with one foot', to date two people at the same time; two-timing in Cantonese
daapˍ₆踏loengˏ₅兩tauˎ₄頭syunˎ₄船简 踏两头船
Mandarin Pinyin: ta4 liang3 tou2 chuan2
Meaning of 踏兩頭船
nounliterally: 'stepping on two ships with one foot', to date two people at the same time; two-timing