to communicate and have conspiring agreement with others before the event
Definitions (粵典–words.hk)
動詞
串謀做壞事 to collaborate in a scheme; to conspire
班友奸到死，幾個人一路打牌一路係咁打聾通，分明呃錢。
班友奸到死，几个人一路打牌一路系咁打聋通，分明呃钱。
baan1 jau2 gaan1 dou3 sei2, gei2 go3 jan2 jat1 lou6 daa2 paai2 jat1 lou6 hai6 gam2 daa2 lung4 tung1, fan1 ming4 ngaak1 cin2. Those guys are so crooked. They kept giving each other secret signals while playing mahjong. It's pretty clear they were trying to cheat others out of their money.
佢兩個打同通，周圍呃人錢。
佢两个打同通，周围呃人钱。
keoi5 loeng5 go3 daa2 tung4 tung1, zau1 wai4 ngaak1 jan4 cin2. They conspired to cheat others out of their money.