一飲而盡

to drain the cup in one gulp (idiom)

one / single / a (article) / as soon as / entire; whole; all; throughout / "one" radical in Chinese characters (Kangxi radical 1) / also pr. [yao1] for greater clarity when spelling out numbers digit by digit

to drink

to give (animals) water to drink

and / as well as / and so / but (not) / yet (not) / (indicates causal relation) / (indicates change of state) / (indicates contrast)

to use up / to exhaust / to end / to finish / to the utmost / exhausted / finished / to the limit (of sth) / all / entirely