A chumpin is a round-faced person with a very chumpinesque smile, i.e. a smile with puffy cheeks that makes them look slightly dopey but endearing all the same.
what a chumpin she is!
by Bird LAWKAMM October 03, 2006
A situation, place, or person and the term varies and could mean empty, lame, or unexciting
Walking into a restaurant and seeing it empty, This place is Chumpin
by Happy-Meal April 14, 2011