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lu·mi·nol

(lmə-nôl′, -nŏl′)

A yellow crystalline organic compound, C₈H₇N₃O₂, that exhibits blue chemiluminescence when activated by an oxidizing agent. Luminol can be used in forensic investigations to detect blood stains, in which case the iron in hemoglobin acts as the activating oxidant.

[Latin lūmen, lūmin-, light; see LUMEN + -OL².]

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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