thumb

Definitions

General English

Electronics

  • Within a scroll bar, the box that can be moved in the desired direction, to navigate within a file or window. For instance, by utilizing a mouse to slide the elevator downwards within a vertical scroll bar, a user advances further ahead in a displayed document. Also called elevator, or scroll box.

Media Studies

  • verb to glance through the pages of a book or magazine

Medical

  • noun the short thick finger, with only two bones, which is separated from the other four fingers on the hand

Origin & History of “thumb”

The thumb is etymologically the ‘swollen’ part – an allusion to its greater thickness than the other fingers. along with its relatives German daumen and Dutch duim, it goes back to a prehistoric west Germanic *thūmon. this in turn can be traced to Indo-European *tum- ‘swell’, which also produced English tumour and tumult. The b in thumb appeared in the early middle English period, when it was still a two-syllable word (thumbe), and at first was pronounced, but it has fallen silent over the centuries.
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