A swig is a large gulp or mouthful of a drink, usually taken quickly. When you take a swig of water after running around at recess, you're not sipping daintily: you're taking a big, satisfying drink. Picture a pirate in a movie tilting back a bottle and taking a hearty swig of something, or a construction worker pausing to take a swig from their water bottle on a hot day.

The word suggests drinking with energy and purpose, not the careful, polite sips you might take at a formal dinner. You might take a swig of lemonade on a sweltering afternoon, or see someone take a swig of milk straight from the carton.

People also use swig as a verb: to swig something means to drink it in that same quick, hearty way. The word carries a casual, informal feeling: you swig water from your canteen on a hike, but you wouldn't say you swigged soup at a restaurant table.