すいたい 衰退 Common word Wanikani level 49 Play audio LinksSentence search for 衰退Sentence search for すいたいSentence search for 衰頽Kanji details for 衰 and 退Edit in JMdict Noun, Suru verb, Intransitive verb1. decline; degeneration; decay; waning; ebbingOther forms衰頽 【すいたい】Notes衰頽: Rarely-used kanji form. Discussions Log in to talk about this word.