1. the act of getting totally wasted from drinking too much genny cream ale.
2. the resulting hangover from killing a 30 rack of genesee beer in one night.
3. the unforgivable crime of drinking all the genny selfishly, or of letting it get too warm and thus undrinkable.
Guy 1: Dude, I committed geneseide last night.
Guy 2: I know, you cleansed the fridge's beer population of any remaining genny creams.