Ancient Rome no relation thumbs down
A thumb signal, usually described as a thumbs-up or thumbs-down, is a common hand gesture achieved by a closed fist held with the thumb extended upward or downward in approval or disapproval, respectively. These gestures have become metaphors in English: "The audience gave the movie the thumbs-up" means that the audience approved of the movie, regardless of whether the gesture was made.Ancient Rome
The Latin phrase pollice verso is used in the context of gladiatorial combat for a hand gesture used by Ancient Roman crowds to pass judgment on a defeated gladiator.Context-specific usage
More recently, these gestures are associated with film reviews, having been popularized by critics Gene Siskel and Roger Ebert on their televised review show Siskel & Ebert; the thumb up meaning a positive opinion of a film; the thumb down meaning a negative one. The trademarked phrase "two thumbs up", originally meaning a positive review from both reviewers, has come to be used as an indication of very high quality or unanimity of praise.
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