Hemorrhoids

n. swollen blood vessels near the anus

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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(n. pl.)
Livid and painful swellings formed by the dilation of the blood vessels around the margin of, or within, the anus, from which blood or mucus is occasionally discharged; piles; emerods.
  

Dilated veins around the rectum.

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