A young guy, shy, loner, usually a teenager, often a geek, who does not have a girlfriend and spends far too much time alone, often at home in his bedroom, when other people his age are out having a good time. The implication being that he is wanking or fucking, i.e. "Pumping" his mattress because he can't root a real Sheila. The meaning of the term and it's use might have nothing in common.
An underage drinker (under 18) is in a bar and bumps, into a grown man who shouts at him, "Piss off, you little mattress pumper".
by sbjkd January 19, 2009

An act performed usually by two female strippers, with an observer. The observer lays on the floor, then the first stripper lays face up on the observers chest so that his head is pretty much between her legs. The 2nd stripper then lays face down 69 style on top and proceeds to perform cunnilingus on the first stripper while the observer gets an up-close view.
by Dragon887 December 17, 2007

Nickname for Paris Hilton.
by Bill gronos June 11, 2006

When a group of girls spend the night with a group of guys, the girl that is left over (the one that did not score) ends up sleeping on a mattress in the living room.
by craxyvixen December 16, 2008

what you call a person with a square, large body.
let me reiterate: YOU HAVE NO CURVES!
also, people sleep on you a lot because you're a slut.
let me reiterate: YOU HAVE NO CURVES!
also, people sleep on you a lot because you're a slut.
girl one: you look like you have a mattress body in that dress. only spongebob would be into you!
girl two: what the fuck? you're the one with the mattress body you whore!
girl three: oh boy! i didnt know we talked this way!
girl two: what the fuck? you're the one with the mattress body you whore!
girl three: oh boy! i didnt know we talked this way!
by spongebobmattressbody-pants June 20, 2011

People who jump from one relationship to another with ease and have low self esteem, no standards, or very low standards when it comes to choosing a significant other.
Jennifer and Dean are mattress hopers who left their significant others to be with each other. They did that before with their exes and will do it again to each other.
by Justasmartgirl July 7, 2011

by stephette February 17, 2010
