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len·ti·vi·rus

(lĕntĭ-vī′rəs)

n. pl. len·ti·vi·rus·es

Any of a group of retroviruses of the genus Lentivirus that cause diseases with a long latent period and a slow, progressive course. HIV is a lentivirus.

[New Latin Lentivīrus, genus name : Latin lentus, slow + VIRUS.]

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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