spirit, mind, air, atmosphere, mood
気 centers on an invisible but vital force or substance: the spirit or mind that animates living things, the air or atmosphere that surrounds us, and the mood or feeling that pervades a situation.
spirit; mind; heart
feeling; sensation; mood; state of mind
popularity; public favor
lively; full of spirit; energetic; vigorous; vital; spirited
feeling; mood
to notice; to realize; to realise; to become aware (of); to perceive; to sense; to suspect
seriousness; earnestness; truth; sanctity
electricity
atmosphere; mood; ambience; ambiance; aura; feel
illness (usu. excluding minor ailments, e.g. common cold); disease; sickness
air; atmosphere
carefree; buoyant; lighthearted; sprightly
weather
favorite; favourite; pet (e.g. teacher's pet)
in one go; in one gulp; in one breath; without stopping; without pausing; without a rest; in one sitting; at a stretch
courage; bravery; valour; valor; nerve; boldness
will (to do something); drive; motivation; enthusiasm; eagerness
cool; calm; composed; unconcerned; nonchalant; unmoved; indifferent
(air) temperature
extramarital sex; affair; fooling around
-like; -looking; -looked; tending to ...
sensation; feeling
madness; insanity; madman; lunatic; crazy person
madness; insanity
気 is the modern Japanese simplified form of 氣. The older form combines 气 (vapor, breath) with 米 (rice), suggesting steam rising from cooking rice, which came to represent vital energy or spirit. The modern simplification replaces the inner 米 with a simple 㐅.
The outer shape 气 looks like a puff of air or steam rising. Inside, the simple 㐅 can be seen as a marker of something intangible. Together, 気 is the invisible spirit, mood, or atmosphere that fills a space.
For キ, imagine a key (キー) that unlocks the invisible energy of the room: key -> キ, and that key lets the spirit flow.