bone up

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bone up (third-person singular simple present bones up, present participle boning up, simple past and past participle boned up)

1. (intransitive, slang) To study or cram, especially in order to refresh one's knowledge of a topic.
   • 1913, William Christian Schmeisser, Are You Going To College?, page 132:

     Information acquired in that way, makes an impression ; this "boning" up for an examination is all right as a finishing touch, but it will not last.

   • 1914, Kathleen Norris, chapter 2, in Saturday's Child:

     Here's your chance to bone up on the segregating, or crediting, or whatever you call it.

   • 2004, Kate Novack, "Fashion Literacy," Time, 14 Sep.,

     Now is the perfect time to bone up on your fashion history.

   Synonym: read up

• In contemporary usage bone up is intransitive and often followed by on, or for, but in dated usage it was sometimes used with a direct object, as in:

1921, P. G. Wodehouse, Indiscretions of Archie, ch. 17,

My idea was to get this book and coach the dear old chap. Rehearse him, don't you know. He could bone up the early chapters a bit and then drift round and try his convincing talk on me.