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tat² also TAT

(tăt)

1. A gene in the AIDS virus that stimulates the host cell to replicate genetic components of the virus.

2. The protein encoded by this gene that is a potent transactivator of viral replication.

[t(rans)a(c)t(ivator) (gene).]

tat³ or tatt

(tăt) Informal

A mark or design made on the skin; a tattoo.

tr.v. tat·ted, tat·ting, tats or tat·ted or tat·ting or tatts

To tattoo.

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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