An event put on by gay men (or women), much like a baby shower, to celebrate the conception and eventual birth of a child. At the center of the event is typically a fruit fly or same-sex couple. Activities at such an event include traditional baby shower games and decor typically includes brightly colored favors. Drinking heavily is not frowned upon at such an event.
The gayby shower last week was the first shower I've ever been to where the bears were covered in pink glitter but weren't stuffed.