Could it be "Hey Lah-di"? Chorus goes "Hey lah-di lah-di lah-di, hey lah-di lah-di lo" twice. Verses are made up by those present, using and rhyming with the name of someone else there. Example: "I know a guy whose name is Fred, hey lah-di lah-di lo, The girls say his poor thing is dead, hey lah-di lah-di lo", followed by the chorus. (Apologies to all the Freds out there, just the first rhyme that came to mind tonight.) Gets as bawdy as the crowd dares. Copious amounts of booze help.