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lor·at·a·dine

(lôr-ătə-dēn′)

A nonsedating antihistamine, C₂₂H₂₃ClN₂O₂, used to treat allergic rhinitis and other allergic disorders.

[(CH)LOR(O)- + (az)atadine, antihistamine from which it is derived (probably alteration of AZO- + (HEP)TA- + -(I)D(E) + -INE²).]

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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