add nonfissionable material to (fissionable material) so as to make unsuitable for use in an atomic bomb
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modify (as a native protein) especially by heat, acid, alkali, or ultraviolet radiation so that all of the original properties are removed or diminished
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make (alcohol) unfit for drinking without impairing usefulness for other purposes
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Denature \De*na"ture\, v. t. [De- + nature.] To deprive of its natural qualities; change the nature of. [Webster 1913 Suppl.]
2. to render (ethyl alcohol) unfit to drink by adding in toxic or unpalatable substances (such as benzene or pyridine) which nevertherless permit alcohol to be used as a solvent. [PJC]
3. modify the tertiary structure of (a protein or nucleic acid) so as to reduce or destroy its characteristic biological activity.
Note: Bioactive macromolecules such as enzymes or DNA may be denatured by heat, acid, alkali, or solvent treatment; the extent of such treatment required to denature a molecule varies with the specific compound. In some cases the denatured molecules may regain their original properties (renature) by other treatments. Denaturation may also cause a change in the physical properties of such molecules, e.g. proteins may become insoluble in water. [PJC]
Denature \De*na"ture\, v. i. To become denatured. [PJC]