wane1
v.
- (of the moon) have a progressively smaller part of its visible surface illuminated, so that it seems to decrease in size.
- become weaker.
Phrase
- on the wane
becoming weaker or less vigorous.
Etymology
OE wanian ‘lessen’, of Gmc origin; rel. to L. vanus ‘vain’.
wane2
n.
the amount by which a plank or log is bevelled or falls short of a squared shape.
Derivative
Etymology
C17: from wane1.