Английский словарь американских идиом - for keeps

{adv. phr.} 1. For the winner to keep. * /They played marbles for keeps./ 2. {informal} For always; forever, * /He left town for keeps./ Syn.: FOR GOOD. 3. Seriously, not just for fun. * /This is not a joke, it's for keeps./ - Often used in the phrase "play for keeps". * /The policeman knew that the robber was trying to shoot him. He was playing for keeps./