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neu·ro·fi·bril

(nr′ə-fībrəl, -fĭbrəl, nyr′-)

Any of the long, thin, microscopic fibrils that run through the body of a neuron and extend into the axon and dendrites.

neu′ro·fibril·lar′y (-brə-lĕr′ē) 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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