The act of flossing one's teeth with the hair that is near or on the asshole of one's partner, so that the "chuncher" receives a tooth flossing and the "chunchee" receives a dingleberry removal. Because of the mouth-to-asshole proximity that is involved, a chunch is often accompanied with a friendly rimjob or an ass trumpet.
An affectionate name for friend, a buddy, a pal who may or may not be a little bit of a muppet but you love them for it. Based on the noise your cheeks make when pinched in an affectionate manner, similar to Chimp.
1) Victoria, you chunch you nearly took my eye out opening that bottle of wine.