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spirit; mind; heart
nature; disposition
intention; mind; will; motivation
mood; feelings
consciousness
care; attention; consideration; worry
interest
(the) air; atmosphere
ambience; atmosphere (of); air (of); mood
fragrance; aroma; flavour; taste
qi (in traditional Chinese philosophy and medicine); chi; ki
「気」 has other readings with different meanings.
彼は気が短い人なんです。
He is a short-tempered person.
小さなことは気にしないでください。
Please don't worry about it.
雨が降りそうだから、気をつけて帰ってね。
It looks like it's going to rain, so be careful on your way back.