Eraser

noun

1. One who erases.
2. A thing used to erase or remove something written or drawn by a pen or a pencil.

   "I have worn out the eraser on this pencil."

3. A thing used to erase something written by chalk on a chalkboard, by marker on a whiteboard, or by some other erasable implement; a chalkboard eraser, whiteboard eraser, etc.
4. An overwriter program used to prevent data recovery.