The whole world has gone butt-wild. An oral and anal sex act where one person stimulates the anus of another person using their mouth. Rimjob is a common slang term for this sex act. The external opening of the rectum. A slang term for a woman with a large, round ass.
The superior aspect of the buttock ends at the iliac crest , and the lower aspect is outlined by the horizontal gluteal crease. The gluteus maximus has two insertion points: The masses of the gluteus maximus muscle are separated by an intermediate intergluteal cleft or "crack" in which the anus is situated. The buttocks allow primates to sit upright without needing to rest their weight on their feet as four-legged animals do.
This article does not cite any sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. November Learn how and when to remove this template message The intergluteal cleft, also known medically by various synonyms and colloquially as the butt crack or ass crack, is the groove between the buttocks that runs from just below the sacrum to the perineum , so named because it forms the visible border between the external rounded protrusions of the gluteus maximus muscles.