Funjacker

A person who is known to ruin the good time being had by others.

See funjack

It was a blast at Duff's Brooklyn tonight, with nary a funjacker in sight to put a damper on things

Funjack

The act of diminishing the fun time had by others, either by design or circumstance.

See also: funjacker and funjacked

I thought we'd never stop laughing, but then Dave's stupidity was a sudden funjack