"Voila!" (4)
'voila' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for bingo that I've seen before include "Popular gambling game in which numbers are called at random" , "Game in which "two little ducks" might be called" , "Housey-housey" , "House!" , "Number game" .)
(Other definitions for presto that I've seen before include "In quick tempo (mus.)" , "Hey ..., said the magician" , "Hey, quickly for a magician" , "Moving quickly" , "quick to score" .)