Answer:

Swollen anal blood vessels

Swollen blood vessels in and around the anus that cause itching, pain, and sometimes bleeding.  

From the AHD

hemorrhoid
SYLLABICATION: hem�or�rhoid
PRONUNCIATION: HEM-eh-roid
NOUN: 1. An itching or painful mass of dilated veins in swollen anal tissue. 2. hemorrhoids The pathological condition in which such painful masses occur. Also called piles.

They are painful, swollen veins in the rectum or anus.
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First answer by Ranger22. Last edit by Jbaker5791. Contributor trust: 636 [recommend contributor recommended]. Question popularity: 36 [recommend question].