BILLY Meaning of BILLY in English 1. n. (pl. -ies) (in full billycan) orig. Austral. a tin or enamel cooking-pot with a lid and wire handle, for use out of doors. Etymology: perh. f. Abor. billa water 2. n. (pl. -ies) BILLY-GOAT. Oxford English vocab. Оксфордский английский словарь. 2012