Entry 1 sense Webster, 1913 Water snake /wôt'-ẽr snāk/ · Wa·ter snake · IPA 01 A common North American colubrine snake (Tropidonotus sipedon) which lives chiefly in the water. 1. A common North American colubrine snake (Tropidonotus sipedon) which lives chiefly in the water.(Zool.)