king for a day—a person whose fame, popularity, etc., is but short-lived:
- Superintendent Michael Snow was king for a day in Middlefield this summer, serving as grand marshal of the town’s bicentennial parade.
king of day, the—(poetic) the Sun:
- I have never seen Italy’s far-famed sky, but I do not think it could surpass that evening sunset. The king of day sinking into the bosom of Silver Lake…