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dor·nase al·fa

(dôrnās′ ălfə, -nāz′)

A genetically engineered enzyme used to hydrolyze the DNA in bronchial mucus, facilitating its expectoration, in the treatment of cystic fibrosis.

[(recombinant human) d(e)o(xy)r(ibo)n(ucle)ase (1) + alteration of ALPHA.]

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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