rub out

verb3

1. •
   To delete or erase or remove (something) by rubbing, especially with a rubber (eraser).

   • The teacher wanted to rub out the chalk marks on the blackboard.
2. •
   (slang) To kill, especially to murder.

   • It was just a week to the day since Mr. Martin had decided to rub out Mrs. Ulgine Barrows. — 1942
3. •
   (no longer used) To get by; to live.

   • The first will understand but little of them, the latter over much; they might perhaps live and rub out in the middle region. — 1603