夏日 なつび Meanings Noun hot summer day day on which the temperature reaches at least 25°C See also: 真夏日 (まなつび). See also: 猛暑日 (もうしょび). Kanji 夏 summer. Read as なつ. 日 day. Read as ひ. Words containing 夏日 真夏日 (まなつび) day on which the temperature rises above 30°C Jinuma: Japanese Dictionary · Word lists