slip away

— phrasal verb with slip

/slɪp/ verb (-pp-)

Definition

C2 to leave secretly: He slipped away while we were all sleeping. C2 If a period of time slips away, it passes quickly: Time was slipping away and she had to make a decision soon. C2 If someone's power or the possibility of someone winning or achieving something slips away, it disappears: Political power was really in their hands and they let it slip away.

(Definition of slip away from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)