What is the meaning of Undress?

To remove one's clothing.

To remove one’s clothing.

To remove the clothing of (someone).

To strip of something.

To take the dressing, or covering, from.

Partial or informal dress for women, as worn in the home rather than in public.

Informal clothing for men, as opposed to formal or ceremonial wear.

Now more specifically, a state of having few or no clothes on.

Source: wiktionary.org