What does wane mean?

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From our dictionary:

wane

Pronunciation: (wAn), [key]
v., waned, wan•ing,
n.


v.i.
1. to decrease in strength, intensity, etc.: Daylight waned, and night came on. Her enthusiasm for the cause is waning.
2. to decline in power, importance, prosperity, etc.: Colonialism began to wane after World War II.
3. to draw to a close; approach an end: Summer is waning.
4. (of the moon) to decrease periodically in the extent of its illuminated portion after the full moon. Cf. wax 2 (def. 2).

n.
1. a gradual decrease or decline in strength, intensity, power, etc.
2. the drawing to a close of life, an era, a period, etc.
3. the waning of the moon.
4. a period of waning.
5. a defect in a plank or board characterized by bark or insufficient wood at a corner or along an edge, due to the curvature of the log.
6. on the wane, decreasing; diminishing: The popularity of that song is on the wane.