Anal sphincter

The anus is the final portion of the large intestine, and consists of muscles controlling the outlet (the anal sphincter) and skin covering them. The internal mucosa of the intestines join with the external skin at the anus.

The rectum is that portion of the large intestine lying immediately inside the anus. It is somewhat ill-defined anatomically, but is generally considered to end at the relatively sharp turn some 10 inches or so up from the anus.

Little lubrication is produced by the anus or rectum, and so insertion of anything into them must beaccompanied by externally supplied lubrication. This is a major difference from the vagina, which is self-lubricating in normal circumstances.

Colloquial

• UK : arsehole
• US : asshole

See also

• Butt plug
• Prostate
• Anal sex