rump

noun

• 1the hind part of the body of a mammal or the lower back of a bird: the harrier is distinguished by its prominent white rump he slapped the horse on the rump [mass noun]:a medium-rare slice of rump
• chiefly humorous a person’s buttocks: he removed his hand from Shirley’s rump

• 2a small or unimportant remnant of something originally larger:once the profitable enterprises have been sold the unprofitable rump will be left [as modifier]:the rump Yugoslavia
• (the Rump)short for Rump Parliament.