They were gatherings.
Seriously. We coined the term, but the concept was done before us, by TickleChgo, at earliest documented event.
The events were social parties that COULD have play, as opposed to play parties, which implied you had to play or you were at the wrong place. The point was and is to meet others into this. Drinking booze was discouraged and still is, largely, at the events. A) it dulls self-control and B) who wants to forget anything at these? Never really had an issue with preventing drinking, save one cat who came loaded to an event that allowed booze. The play was easy. Always had several people volunteering to play.
They happened in homes, mine and others. They happened in hotel rooms and suites. They happened in clubs. They've happened on this continent and in England, organized by me, and as well by others.
They used to happen monthly in CA. Times changed. Economy got bad. Club burned down. No one has a home available in SoCal. It lulls.