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bone up

British  

verb

  1. informal (adverb; when intr, usually foll by on) to study intensively

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
bone up Idioms  

  1. Study intensely, as in I'll have to bone up on my Spanish if I'm to pass the language requirement. The verb bone alone was used in this sense from the mid-1800s on, up being added later. [Slang; late 1800s]

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.