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Partial calque of French sur le qui-vive (“in a state of heightened vigilance”).
Etymology from Wiktionary, CC BY-SA 4.0.
on the qui vive
Today it means: In a state of heightened vigilance, especially prior to battle. Full definition →
Today it means: In a state of heightened vigilance, especially prior to battle. Full definition →
Partial calque of French sur le qui-vive (“in a state of heightened vigilance”).
Etymology from Wiktionary, CC BY-SA 4.0.