quaff (kwŏf, kwāf, kwôf) v.
quaffed, quaff·ing, quaffs
v.
tr. To drink (a beverage) heartily: quaffed the ale with gusto. v.
intr. To drink a liquid heartily: quaffed from the spring. n. A hearty draft of liquid.
1520 (implied in quaffer), perhaps onomatopoeic, or perhaps from Low Ger. quassen "to overindulge (in food and drink)," with -ss- misread as -ff-. The noun is from 1579.