defacement

An act of defacing; an instance of visibly marring or disfiguring something.

Some consider the defacement of the Sphinx to be the most egregious crime of Napolean's campaigns.

An act of voiding or devaluing; nullification of the face value.

The soldiers found a variety of creative uses for their payment scrip after its defacement to scrap paper; some used it as toilet paper.

A symbol added to a flag or coat of arms to change it or make it different from another.