酷暑日 こくしょび Meanings Noun day on which the temperature rises above 40°C (official meaning) day on which the temperature rises above 35°C; extremely hot day See also: 猛暑日 (もうしょび). Kanji 酷 harsh. Read as コク. 暑 hot. Read as ショ. 日 day. Read as ひ. Jinuma: Japanese Dictionary · Word lists