史し上じょう空くう前ぜんMeaningsNoun1. unprecedented in history; unheard-of; epoch-making (Yojijukugo)Kanji used史history上above空empty air前in front ofComposed of史し上じょうin history; ever; historicalNo-adjective空くう前ぜんunprecedented; record-breakingNo-adjective