A person who "isn't a bigot" but whose opinions, actions, voting patterns, and policy preferences are indistinguishable from those of bigots.
"Yo, you know who I hate? Immigrants. And blacks. And Muslims. I'm going to go vote for Donald Trump now."
"Dude, don't be a bigot."
"I'm not a bigot!"
"Okay, whatever, then don't be a rumpot."
A somewhat derogatory way of referring to a female who is immediately available for sex. It can be qualified to give a more accurate description of the female in question e.g. “a nice bit of rumpo” would be a female who is attractive as well as available, while “a right bit of old rumpo” would be a female who is available to anyone and his dog.
A hybrid from rump which refers to a woman's ass and the sound Reuber's camshaft made from his 74 whatever hot rod. Rumpo meaning sex, and one of the greatest bands ever, Rush. Add brush in there referring to a rump brush. This was established around 1986 or so. A fun word to look at and say.