An invitation-only party at an sf convention. Typically a room party held by individuals or groups for their friends or members or a publishers' party aimed at pros. When held for or by pros, such a party may be referred to as the "Secret Pro Party."
Anyone who stumbles across a closed-door party may ask to be admitted, but should take a refusal graciously.
|From Fancyclopedia 2 ca 1959|
|Closed-Door Pro Party
That's what they are when you're on the outside.
|This is a fanspeak page. Please extend it by adding information about when and by whom it was coined, whether it’s still in use, etc.|