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A term to describe when a persons thigh and butt is not distinguisable. This is caused by either fat thighs or a flat butt.
google search: butthigh.
A fat person with rolls under their butt, which makes it hard to tell where the butt ends and the thigh begins.
A skinny person with a small flat butt, which makes the whole backside look like a flat brick.
by Khang Nguyen January 20, 2008