look up any word, like the eiffel tower:
A very large jerkoff-half dinosaur like human of the Upper Cretaceous Period of North America, characterized by having strong wrists and a large head. Also know to some Canadian dwellers as jerkoffskie
Jerkasaurus is owning up!
by Last_Assassin January 14, 2004
the king of jerks - total idiot - loser
you're a real jerkasaurus.
by j.bowen January 01, 2007
A dinosaur sized jerk.
Lindsay is a jerkasaurus!
by Sef1989 April 19, 2011
A person who has exhibited abnormally large amounts of rudeness or has said something especially heinous.
Kelly walks into the room...

"Well hello Kelly McFatass! Quick grab a chair! Outta breath already, aren't ya?"- Ian

"Ian you are a jerkasaurus!!!"- Kelly
by K-rex15 May 16, 2012