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cyst

(sĭst)

1. An abnormal membranous sac in the body containing a gaseous, liquid, or semisolid substance.

2. A sac or vesicle in the body.

3. Biology A small capsulelike sac that encloses certain organisms in their dormant or larval stage.

4. Botany A thick-walled resting spore, as in certain algae or fungi.

[New Latin cystis, from Greek kustis, bladder; see kwes- in the Appendix of Indo-European roots.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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