A shout of approval, used at the moment a performance ends — after a song, a solo, a play, a piece of dancing. It belongs to the concert hall and the theatre far more than to daily life, and it is usually shouted, not said quietly. Away from the stage people do use it, but then it is often half-joking or a little grand, as when a teacher says 'Bravo!' to a student who finally got a hard question right. It works as a noun too: 'shouts of bravo', 'the bravos of the crowd'. Strict opera-goers keep the Italian endings — 'bravo' for one man, 'brava' for one woman, 'bravi' for a group — and you will hear that in a serious opera house, but in ordinary English 'bravo' is used for everyone and nobody minds. Quite separately, 'Bravo' is the letter B in the spelling alphabet pilots and soldiers use ('Alpha, Bravo, Charlie'), which is why you hear it in aeroplane and army films.