4
decreasing(adjective, lessening, declining, shrinking, lowering)
4
decrease(noun, drop, cut, decline, fall)
4
deteriorating(verb, adjective, weakening, lessening, worsening)
4
deterioration(noun, drop, decline, fall, decrease)
4
downgrade(noun, drop, fall, failure, deterioration)
4
falling(adjective, weakening, lessening, declining, worsening)
4
on the wane(expression, adjective, idiom)
4
shriveling
4
sinking(noun, verb, adjective, drop, decrease)
3
abating(verb, adjective, lessening, declining, shrinking)
3
aging(noun, decrease, stale, ebb, senescent)
3
blight(noun, decline, deterioration, degeneration)
3
collapsing(verb, deteriorating)
3
decay(noun, drop, decline, fall, decrease)
3
declination
3
doting
3
dropping(verb, adjective, declining, shrinking, lowering)
3
effete
3
failure(noun, drop, fall, deterioration, falloff)
3
moribund
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APASmart Define. (2015). waning thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/waning/thesaurus/synonyms
ChicagoSmart Define. 2015. "waning thesaurus" https://smartdefine.org/waning/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, waning thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/waning/thesaurus/synonyms>.
MLASmart Define. "waning thesaurus" 13 April 2015. Web. 23 September 2026. <https://smartdefine.org/waning/thesaurus/synonyms>