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Bt.

abbr.

baronet

abbr.

Bachelor of Theology

(bētē)

A soil bacterium (Bacillus thuringiensis) that produces proteins toxic to certain insects. It has been used as an insecticide, and genes for the toxins have been incorporated into genetically modified crop plants to control insect pests.

adj.

Having and expressing toxin-producing genes from the bacterium Bacillus thuringiensis: Bt cotton; Bt crops.

[From New Latin B(acillus) t(huringiēnsis), species name.]

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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