look up any word, like sparkle pony:
A gernasium is a word used to describe something that doesn't have something to easily compare it to, or can be used when you are at a loss for adjectives in the midst of making an important point. It can be used to bolster your pseudo-intelligence by using a made-up, yet smart sound word.
"It was freezing today..it was easily as cold as..a gernasium."

"Did you see the way that gymnast spun? It was something of a gernasium!"

"How do you feel about bread pudding?"
-" The truth is that bread pudding is something of a gernasium for me."
by sdcabp May 04, 2011