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ex·ten·som·e·ter

(ĕk′stĕn-sŏmĭ-tər)

An instrument used to measure minute deformations in a test specimen of a material.

[EXTENS(ION) + -METER.]

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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