thumb

plural thumbs · alternative obsolete thum · alternative obsolete thume · alternative obsolete thumbe

1. The shortest and thickest digit of the hand that for humans has the most mobility and can be made to oppose (moved to touch) all of the other fingers.
2. computingThe part of a slider that may be moved linearly along the slider.

   a scroll-bar thumb

3. InternetcolloquialA thumbnail picture.
4. A top hatch plate for covering an excavator bucket, used to keep material in the digger bucket after scooping it up, and not letting it spill out.

present singular third person thumbs · participle present thumbing · participle past thumbed · past thumbed · alternative obsolete thum · alternative obsolete thume · alternative obsolete thumbe

1. transitiveTo touch or cover with the thumb.

   to thumb the touch-hole of a cannon

   1 more example

   News agencies reported Lavrov had been sent to hospital for a checkup, only for the Russian foreign ministry to rush out a picture of Lavrov in shorts, sporting an Apple watch and Jean-Michel Basquiat-inspired T-shirt, thumbing his notes for his first address at the summit on Tuesday.

   2022 November 15, Patrick Wintour, “Sergei Lavrov, a fixture of Russian diplomacy facing his toughest test in Ukraine”, in The Guardian

2. transitiveTo turn the pages of (a book) in order to read it cursorily.

   thumb through

   2 more examples

   I thumbed through the book and decided not to bother reading it all.

   It is also disconcerting when you suddenly realise that the driver isn't steering, but may be thumbing over his Customs papers with his feet up.

   1948 March and April, “Notes and News: Lines in County Donegal”, in Railway Magazine, page 129

   Synonyms: peruse, flip through, browse, leaf, page, peruse

3. To gesture with the thumb, for example when flagging a ride.

   Oh, look! There’s a car coming! Thumb-no, wave. They probably don’t understand thumbing.

   1977, Diana Wynne Jones, Charmed Life

4. lifestyleTo hitchhike.

   So I started thumbin' back east, toward my hometown.

   2 more examples

   Bobby thumbed a diesel down, just before it rained.

   1969, Kris Kristofferson, Fred Foster, Me and Bobby McGee

   Thumbed a diesel down, outside a cafe.

   1980, Kye Fleming, Dennis Morgan, Smoky Mountain Rain

5. To soil or wear with the thumb or the fingers; to soil, or wear out, by frequent handling.

   He gravely informed the enemy that all his cards had been thumbed to pieces, and begged them to let him have a few more packs.

   1849–1861, Thomas Babington Macaulay, chapter XIII, in The History of England from the Accession of James the Second, volume (please specify |volume=I to V), London: Longman, Brown, Green, and Longmans, →OCLC

6. To manipulate (an object) with the thumb; especially, to pull back the hammer or open the cylinder of a revolver.

   Andy opened the revolver, thumbed in a cartridge.

   2015, Don Fitzsimmons, If You Need a Laugh

   2 more examples

   Fargo palmed out his own revolver, thumbing back the hammer as the barrel came up.

   2009, Jon Sharp, The Trailsman #337: Silver Showdown

   Rainford reached down and found the revolver. Thumbing the cylinder open, he inspected the load.

   2015, Tony Monchinski, Bad Men (I Kill Monsters Book 3)

7. To fire (a single action revolver) quickly by pulling the hammer while keeping the trigger depressed.

   To thumb a single-action revolver, hold down the trigger and use the thumb on the same hand to fire the gun by manipulating the hammer.

   2011, Hans-Christian Vortisch, GURPS Tactical Shooting, page 14

1. informalThe eastern part of the Lower Peninsula of Michigan, United States (the "Mitten").

   Turnip Rock is located in a portion of eastern Michigan dubbed the Thumb, where 140 miles of coastline and waterfront towns offer a variety of outdoor activities, including biking, walking and kayaking.

   2018 July 17, Autumn Spanne, “Check out these crazy rock formations across the United States”, in CNN