What is "qui vive"

Qui vive \Qui` vive"\ (k[-e]` v[-e]v"). [F., fr. qui who + vive, pres. subj. of vivre to live.] The challenge of a French sentinel, or patrol; -- used like the English challenge: ``Who comes there?''

To be on the qui vive, to be on guard; to be watchful and alert, like a sentinel.

1726, in on the qui vive "on the alert," from French qui voulez-vous qui vive? sentinel's challenge, "whom do you wish to live," literally "(long) live who?" In other words, "whose side are you on?" (The answer might be Vive la France, Vive le roi, etc.).

n. a state of heightened vigilance, especially prior to battle

n. condition of heightened watchfulness or preparation for action; "bombers were put on alert during the crisis" [syn: alert]