The act of two males standing back to back with a dildo in eachothers assholes. Similar to scissoring but in a homosexual way. If u look closely it looks like a dumbbell ready to hold by the handle and lift up over ur head and rip those gays a new one.
Today I saw my daddy and my other daddy doing the dumbbell in my bedroom with my sissy dildo.
by Dumbbell December 15, 2014
1 more definition
someone who denies they like pot and bums around all the time with nothing else better to do.
"I'm a dumbbell, I've watched anime all day."
by s**g October 22, 2008