noun
one breath; in one go; without stopping
Often used adverbially as 一気に to mean doing something all at once, without pausing. The standalone noun 'one breath' is less common in modern Japanese.
彼はビールを一気に飲み干した。
He downed the beer in one go.
一気に仕事を片付けて
Let's finish the work all at once.
interjection
chug!; drink!
Party cheer chanted repeatedly to encourage someone to down a drink in one go.
「いっき！いっき！」とみんなが叫んだ。
Everyone shouted, 'Chug! Chug!'