宙返り
ちゅうがえり · chuugaeri · JLPT N1 · noun
somersault
宙 — roof 宀 + 由 (phonetic)
宙 is a semantic-phonetic compound: the roof radical 宀 suggests space or dwelling, while 由 supplies the sound. Originally referring to the ridgepole of a roof, it came to mean 'time' or 'eternity,' and pairs with 宇 (space) in 宇宙 'universe.'