chew at

chew (away) at (something)

To chew on something repeatedly or for a length of time. The baby has been completely miserable lately, except for when he's chewing away at a teething ring.
See also: chew
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

chew (away) at something

to gnaw or chew something for a period of time. The puppy chewed away at the leather belt all night.
See also: chew
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
TODAY understands that Khoo has received a sum - amounting to thousands - from Chew at the carpark during the Chinese New Year holiday, in exchange for facilitating an arrangement with boatman Tan Poh Teck.
Your dog will probably dig, claw, and even chew at your foot to try to get the treat.