Bravo

Bravo is an Italian word meaning (literally) brave or (figuratively) well-done.

Now in Italian, generally speaking, masculine words finish with 'o' ('i' for plural) and feminine words finish with 'a' ('e' for plural), though there are exceptions.

Bravo is not an exception. Therefore, for a male dancer (ballerinO) you would holler 'bravO', and for a female dancer (ballerinA) one would yell, 'bravA'. For a group of male or mixed dancers you would use 'bravi' and for a group of female dancers you would use 'brave' (pronouncing the 'e' like in 'bed').

Hope that cleared it up for you!