waning

nouns

a gradual decrease in magnitude or extent
"the waning of his enthusiasm was obvious"; "the waxing and waning of the moon"
waning
antonym
waxing
is derived from
wane
is derived from
wane
is derived from
wane
is a type of (narrower)
a change downward
"there was a decrease in his temperature as the fever subsided"; "there was a sharp drop-off in sales"
decrease, drop-off, lessening

adjectives

(of the Moon) pertaining to the period during which the visible surface of the moon decreases
"after full moon comes the waning moon"
waning
antonym
waxing