よふ 夜更かし Common word JLPT N1 LinksSentence search for 夜更かしSentence search for よふかしSentence search for 夜更しSentence search for 夜ふかしKanji details for 夜 and 更Edit in JMdict Noun, Suru verb, Intransitive verb1. staying up late; keeping late hours; sitting up late at night; nighthawkOther forms夜更し 【よふかし】、夜ふかし 【よふかし】 Discussions Log in to talk about this word.