( informal ) to try to learn about sth or to remind yourself of what you already know about it :
She had boned up on the city's history before the visit.
( informal ) to try to learn about sth or to remind yourself of what you already know about it :
She had boned up on the city's history before the visit.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005