Swig

wiktionary

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Unknown, mid 16th c. Perhaps connected with Old English swelgan(“to swallow”).

etymonline

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swig (n.)

1540s, "a drink, liquor," later "big or hearty drink of liquor" (1620s), of unknown origin.

swig (v.)

1650s, from swig (n.). Related: Swigged; swigging.