be all mouth(redirected from is all mouth)
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be all mouth
To be full of boastful, arrogant, or shallow talk without the ability to deliver on such claims He talks a big game, but when it actually comes to asking out a woman, he's all mouth.
be all mouth(British, American & Australian informal) also be all mouth and (no) trousers (British informal)
if someone is all mouth, they talk a lot about doing something but they never do it She says she'll complain to the manager but I think she's all mouth. You're all mouth and no trousers. Why don't you just go over there and ask her out?