a mix of the words bummer and bender (each used to discribe homosexuals) used to discribe a homosexual
by www.myspace.com/hardjamciders November 1, 2009

by aidenmill6 February 28, 2019

Oska"fuck off you bumder".
Alfie smih"what's a bumper".
Oska"it means gay so its a word that describes you".
Alfie smih"what's a bumper".
Oska"it means gay so its a word that describes you".
by Heeeeeeeeeellllllllooooooooo February 19, 2020

When someone in the same photo as you has a really big bum and takes all the attention (bumder) away from your bum.
"You're stealing my bumder"
by Scrunchie Lady July 9, 2018

by Suckmaballs November 27, 2018

Oh, piss off, you bumder
by Immortal Kombat June 12, 2018

by Urbantheturban July 8, 2019
