From WordNet (r) 3.0 (2006) :
make whoopie
v 1: celebrate noisily, often indulging in drinking; engage in
uproarious festivities; "The members of the wedding party
made merry all night"; "Let's whoop it up--the boss is
gone!" [syn: revel, racket, make whoopie, make
merry, make happy, whoop it up, jollify, wassail]