sextastrophy

something very undesirable that occurs during sexual intercourse. almost always shortly followed by the sudden, yet mutually agreed upon permanent separation of the copulating couple.

helen: "what happend with you and Bill? i thought you were still riding him like a wild dragon-steed..."

Betty: "what happened???!!! what HAPPENED???!! well let me tell you about Bill and the 'rusty trampoline' move he tried last night...boy was that a sextastrophy"