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the·oph·yl·line

(thē-ŏfə-lĭn)

A colorless crystalline alkaloid, C₇H₈N₄O₂, derived from tea leaves or made synthetically, used as a bronchodilator primarily to treat asthma and chronic obstructive pulmonary disease.

[New Latin thea, the tea plant (ultimately from Dutch thee); see TEA + PHYLL(O)- + -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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