The definition of a cyst is a closed sac or hollow cavity filled with liquid that develops unnaturally in people, animals or plants.(noun)
When a hollow fluid-filled cavity appears in the tissue of your body where it does not belong, this is an example of a cyst.
See cyst in Webster's New World College Dictionary
Origin: ModL cystis < Gr kystis, sac, bladder < ? IE base *us-, var. of *wes-, to wheeze, blow
Origin: < Gr kystis: see cyst
See cyst in American Heritage Dictionary 4
Origin: New Latin cystis, from Greek kustis, bladder; see kwes- in Indo-European roots.
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