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te·tro·do·tox·in

(tĕ-trō′də-tŏksĭn)

A potent neurotoxin, C₁₁H₁₇N₃O₈, found in many pufferfishes and certain other animals, including some salamanders and crabs.

[Shortening and alteration of New Latin Tetraodōn, pufferfish genus (Greek tetra-, tetra- + New Latin -odōn, -odon (so called because members of the genus have two upper and two lower teeth)) + TOXIN.]

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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