locked up safely somewhere; in prison :
We keep our valuables under lock and key.
I will not rest until the murderer is under lock and key.
locked up safely somewhere; in prison :
We keep our valuables under lock and key.
I will not rest until the murderer is under lock and key.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005