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i·som·er·ism

(ī-sŏmə-rĭz′əm)

1. The phenomenon of the existence of isomers.

2. The complex of chemical and physical phenomena characteristic of or attributable to isomers.

3. The state or condition of being an isomer.

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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