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

Fauxword

A word that is made up for some purpose and used so often, it's actually accepted as part of the vernacular, without much question.

"Come down before Halloween for our SPOOKTACULAR candy sale!"

Spooktacular would be the fauxword