buttocks

Definition

1. The rounded, fleshy, protuberant musculatures at the rear of the pelvis that form the human rump or posterior; that part of the body upon which one sits. The buttocks or nates are made up of fat and three gluteal muscles, the maximus, the medius, the minimus, of which the gluteus maximus, which extends, abducts, and rotates the thigh, is the most important.See buttocks [SYN] for synonyms.
Etymology: From 13 ^th century Middle English buttuc , a strip of land, butt with the diminutive -uc , which took the form -ock in Modern English.

Quotes:

(1) William Shakespeare. All's Well That Ends Well (1604): ' It is like a barber's chair, that fits all buttocks-the pin-buttock, the quatch-buttock, the brawn-buttock, or any buttock.'

(2) Forrest Gump ( Tom Hanks ) about the thing ' That jumped up and bit you ' in Vietnam in Forrest Gump (1994): ' Hit me directly in the buttocks. They said it was a million dollar wound, but the army must keep that money because I still ain't seen a nickel of that million dollars.'