denature

To take away a natural characteristic or inherent property of (a thing or a person).

To add something to (alcohol) that makes it unsuitable for consumption but leaves it suitable for most other purposes.

To alter its original form or state, especially of a protein, by heat, acidity etc.

Of double-stranded DNA, specifically to split into two single strands.

To combine fissile material with nonfissile material in order to prevent its use in an atomic weapon.