能天気 のうてんき Also written 脳天気, ノーてんき, 能転気, ノー天気 Meanings な-adjective, Noun laid-back; carefree; easygoing; thoughtless; happy-go-lucky Kanji 能 ability. Read as ノウ. 天 heaven. Read as テン. 気 spirit. Read as キ. Example sentences 能天気なやつめ。You're happy-go-lucky. Jinuma: Japanese Dictionary · Word lists