barrel of monkeys UK /ˌbæɹ(ə)l‿əv ˈmʌŋkiz/US /ˌbæɹəl‿əv ˈmʌŋkiz/ noun1 •(informal) Someone or something very amusing or funny, fun, mischievous, etc.He thinks he’s a barrel of monkeys, but he’s not particularly entertaining. formsbarrels of monkeys