To delete or erase or remove (something) by rubbing.(verb)
To get by; to live.(verb)
To kill.(verb)
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Use "rub out" in a sentence
"He straightened and turned, brushing his hands together to rub out the dents left by the weight, and showed them the dark, level brows and burning eyes of Brother Urien."
"I could rub out clothes at the wash-tub afore I was at her age."