hemorrhoid

n. abnormally enlarged vein in or near the anus

Hemorrhoids (AmE), haemorrhoids (BrE), emerods, or piles are varicosities or swelling and inflammation of veins in the rectum and anus.
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Hemorrhoid /hem·or·rhoid/ prolapse of an anal cushion, resulting in bleeding and painful swelling in the anal canal. [more]Hemorrhoid - Community and Resources

Noun
1. pain caused by venous swelling at or inside the anal sphincter
(synonym) haemorrhoid, piles
(hypernym) pain, hurting

[HEM-uh-roid]
An enlarged or swollen blood vessel, usually located near the anus or the rectum.