- tweak (v.)
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- "pinch, pluck, twist," usually to the nose, c. 1600, probably from Middle English twikken "to draw, tug, pluck" (mid-15c.), from Old English twiccian "to pluck," of obscure origin; perhaps related to twitch. Meaning "to make fine adjustments" is attested from 1966. Related: Tweaked; tweaking.
- tweak (n.)
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- c. 1600, "a twitch, a pluck," from tweak (v.). As "a fine adjustment" by 1989.