It is usually used as an exclamation.
Vootie originated in 1955 in a Mad Magazine parody where Dave Garroway's chimp (
J. Fred Muggs - who also painted a cover for Mad) takes over the show. Instead of Dave's signoff, "
Peace", the monkey
said "Vootie". It was later used in 1996 as an exclamation in Star Control 3 by a race called the Xchagger.