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mi·ra·cid·i·um (mîr′ə-sĭdē-əm, mī′rə-)
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n. pl. mi·ra·cid·i·a (-ē-ə)
A ciliated larva of a digenetic trematode, which hatches from the egg and enters the first intermediate host, where it develops into a sporocyst or a redia.
[German, from Greek *meirakidion (attested in Latin as mīracidion, one in early adolescence), diminutive of meirax, young girl, young person, lad.]
mi′ra·cidi·al adj.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. 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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