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Me·dus·a (mĭ-dsə, -zə, -dy-)
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n.
Greek Mythology
The Gorgon who was killed by Perseus.

[Middle EnglishMeduse, fromLatinMedūsa, fromGreekMedousa, fromfeminine present participle ofmedein, to protect, rule over; see med- in the Appendix of Indo-European roots.]
(click for a larger image)
Medusa
2nd-century ad mosaic from the Roman baths at
Sousse, Tunisia

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
me·du·sa (mĭ-dsə, -zə, -dy-)
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n.pl. me·du·sas or me·du·sae(-sē, -zē)
A body form of certain cnidarians such as jellyfish, consisting of a dome-shaped structure with a mouth underneath surrounded by tentacles, and in most species constituting the free-swimming sexual stage of the organism.

[LatinMedūsa, Medusa (from the Medusa's snaky locks); see MEDUSA.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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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