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i·so·ton·ic

(ī′sə-tŏnĭk)

adj.

1. Of equal tension.

2. Isosmotic.

3. Having the same concentration of solutes as the blood: an isotonic saline solution.

4. Physiology Of or involving muscular contraction in which the muscle remains under relatively constant tension while its length changes.

[ISO- + Greek tonos, tension; see TONE + -IC.]

i′so·toni·cal·ly adv.

i′so·to·nici·ty (-tə-nĭsĭ-tē) n.

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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