bone up on

== English == === Etymology === (This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.) === Pronunciation === === Verb === bone up (third-person singular simple present bones up, present participle boning up, simple past and past participle boned up) (intransitive, slang) To study or cram, especially in order to refresh one's knowledge of a topic. Synonyms: brush up, review, revise, rub up ==== Usage notes ==== 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: ==== Translations ==== ==== See also ==== ramp up