What does the word deface mean?

Usage examples for deface

  1. It was perfectly apparent that the damage had been done that very day, but he declared that there was no way to prevent it; that he was the only custodian of the place; that there were no guards; that it was impossible for him to be everywhere at once, and that it was easy enough for tourists and other visitors to deface the mosaics with their pocket knives in one of the palaces while he was showing people through the others. – Modern India by William Eleroy Curtis