eraser
n.
"thing that erases writing," 1790, American English, agent noun from erase. Originally a knife for scraping off the ink. As a rubber product for removing pencil marks, from 1858.
〔蒋〕[ras，rad擦，刮，-er表示物] 擦除器(如黑板擦，橡皮等)
〔蒋〕[ras，rad擦，刮，-er表示物] 擦除器(如黑板擦，橡皮等)