1: Done before occurring, or over before starting.

2: Premature ejaculation, abortion, or stillborn baby.
1: Akiva Schaffer: Yo Jorma. did you hear that Andy was with a girl last night... And he jizzed in his pants?!

Jorma Taccone: Yeah! All his sexual encounters are endstantaneous!

2: Dustin Diamond: Hey Robocop, did you hear that Wonder woman had an abortion?!

Robocop: Yeah, that poor kids life was endstantaneous.
by Jim Shooter December 8, 2010
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