Définitions
1.NounThe 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.NounThe part of a slider that may be moved linearly along the slider."a scroll-bar thumb"
3.NounA thumbnail picture.
4.NounA 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.
5.VerbTo touch or cover with the thumb."to thumb the touch-hole of a cannon"
6.VerbTo turn the pages of (a book) in order to read it cursorily."thumb through; I thumbed through the book and decided not to bother reading it all."
7.VerbTo gesture with the thumb, for example when flagging a ride.
8.VerbTo hitchhike."So I started thumbin' back east, toward my hometown."
9.VerbTo soil or wear with the thumb or the fingers; to soil, or wear out, by frequent handling.
10.VerbTo manipulate (an object) with the thumb; especially, to pull back the hammer or open the cylinder of a revolver.
11.VerbTo fire (a single action revolver) quickly by pulling the hammer while keeping the trigger depressed.
12.Verb↑ Douglas Harper (2001–2026), “thumb”, in Online Etymology Dictionary.