rub at

rub at (something)

To exert pressure on and move in contact with something. Make sure not to rub at your eye if you've got something in there—it will only make it more irritated. He rubbed at the coin with a cloth to make it shine a bit brighter.
See also: rub
Farlex Dictionary of Idioms. © 2022 Farlex, Inc, all rights reserved.

rub (away) at something

to chafe or scrape something, repeatedly. The side of his shoe rubbed away at the side of his desk until the paint wore off. Don't rub at your sore. It will get worse.
See also: rub
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
They rub at random locations as a means of demonstrating strength and dominance to other bucks, while avoiding the risk of combat.