1The interjection used when toasting ('Cheers!'); said when clinking glasses together.
みんなで「乾杯！」と言ってグラスを合わせた。
We all said 'Cheers!' and clinked our glasses.
結婚式で新郎新婦に向かって乾杯した。
We toasted the bride and groom at the wedding.
宴会が始まるとすぐに、司会者が乾杯を促した。
As soon as the party began, the host prompted everyone to toast.
2A toast; the act of raising a glass and drinking in honor or celebration of someone or something.
乾杯をする前に、乾杯の音頭をとる人がいる。
Before the toast, someone gives the opening speech that leads into it.
彼は皆に乾杯を促してからグラスを掲げた。
He urged everyone to toast and then raised his glass.
会の最後に全員で乾杯した。
At the end of the event we all made a toast together.
3To drink one's glass dry; to drain a drink (colloquial usage).
彼は気合いでジョッキを乾杯して一気に飲み干した。
He psyched himself up and drank the mug dry in one go.