Bottoms up! 跟cheers 都有干杯的意思。主要区别在于酒喝不喝光的问题。bottoms up的意思是就是把酒都喝光。cheers只是单纯的干杯。
词语详解：
bottoms up
干杯
cheers
int. 举杯敬酒的用语; 谢谢; 再见;
v. 喝彩（ cheer的第三人称单数 ）; 鼓励; 鼓舞;
相关短语：
Bottoms-up Bottles 干杯瓶
bottoms-up marketing 逆向行销
cheer up 使高兴；高兴起来；使振奋
cheer for 为…欢呼，喝彩；给…加油
双语例句
He drank his whiskey almost bottoms up.
他把杯中的威士忌喝得几乎一滴不剩.
Thanks. And to your presence! Bottoms up!
谢谢. 也为你们的到来干杯! 干杯!
Her dancing brought loud cheers, wolf whistles and applause.
她的舞蹈赢来震耳的欢呼声、口哨声和掌声。
"Cheers," he said and winked daringly at her.
“干杯，”他边说边大胆地向她使眼色。