the.com/cyst

A sac that built itself a wall and moved in permanently.

means A closed sac in the body with a distinct membrane, usually filled with fluid, air, or other material, that forms as its own abnormal pocket of tissue.

from From Greek 'kystis,' meaning bladder or pouch — the same root that gave us 'cystitis' and 'cystic.' The Greeks used it for the bladder itself, and later anatomists borrowed the word for any sac-like pocket that didn't belong, carrying the bladder's bag-like shape into the broader medical vocabulary.

definition
Sac of tissue filled with fluid, air, or gunk
most common type
Sebaceous cysts form from blocked oil glands
eviction notice
Many shrink alone, no drama needed
etymology
From Greek kystis, meaning bladder or pouch
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