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ex·ci·to·tox·in

(ĭk-sītə-tŏk′sĭn)

Any of a group of neurologically active compounds, including glutamate and aspartame, that in high concentrations have detrimental excitatory effects on the central nervous system and may cause injury to nerve cells.

[EXCIT(ATORY) + TOXIN.]

ex·cito·tox′ic (ĭk-sītə-tŏk′sĭk) adj.

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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