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phthal·o·cy·a·nine

(thăl′ō-sīə-nēn′, fthăl′-)

A stable blue-green porphyrin-based organic dye, C₃₂H₁₈N₈, or any of several blue-green derivatives containing chelated metals, used in enamels, printing inks, linoleum, and plastics.

[PHTHAL(IC) + CYANINE.]

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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