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sub·stit·u·ent

(səb-stĭch-ənt)

An atom or group substituted for another in a chemical compound.

adj.

Of or relating to such an atom or group.

[Latin substituēns, substituent-, present participle of substituere, to substitute; see SUBSTITUTE.]

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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