Definition of qui vive noun from the Oxford Advanced Learner's Dictionary

 

qui vive

 noun
noun
BrE BrE//ˌkiː ˈviːv//
 
; NAmE NAmE//ˌkiː ˈviːv//
 
 
jump to other results
Word Origin late 16th cent.: from French, literally ‘(long) live who?’, i.e. ‘on whose side are you?’, used as a sentry's challenge.Idioms
on the qui vive
 
jump to other results
paying close attention to a situation, in case something happens He's always on the qui vive for a business opportunity.