KOH, potassium hydroxide, is an ionic compound, not a single element or molecule. Therefore, it doesn't have an oxidation number in the traditional sense.

However, we can look at the oxidation states of its constituent ions:

* K+ (Potassium ion): Has an oxidation state of +1.

* OH- (Hydroxide ion): The oxygen has an oxidation state of -2, and the hydrogen has an oxidation state of +1, making the overall charge of the hydroxide ion -1.

It's important to remember that oxidation states represent the hypothetical charge an atom would have if all bonds were ionic.