To quaff is to drink a lot of something quickly, and usually with pleasure — not a careful sip. People quaff beer, ale, or wine in stories. The word is old-fashioned and a bit playful; nobody at a water cooler says they are quaffing their tea. You meet it in books, jokes, and menus that want to sound hearty and old. There is also a noun: a quaff is that big, eager drink. Though actually, it is almost never an everyday verb in modern speech. If you use drink, gulp, or knock back, people will understand you better — and they will not think you are acting in a play.

痛飲；大口喝（偏書面、帶點幽默）