|1.||Technical name: pollex the first and usually shortest and thickest of the digits of the hand, composed of two short bonesRelated: pollical|
|2.||the corresponding digit in other vertebrates|
|3.||the part of a glove shaped to fit the thumb|
|4.||architect another name for ovolo|
|5.||all thumbs clumsy|
|6.||thumbs down an indication of refusal, disapproval, or negation: he gave the thumbs down on our proposal|
|7.||thumbs up an indication of encouragement, approval, or acceptance|
|8.||under someone's thumb at someone's mercy or command|
|—vb (when intr, |
|9.||(tr) to touch, mark, or move with the thumb|
|10.||to attempt to obtain (a lift or ride) by signalling with the thumb|
|11.||to flip the pages of (a book, magazine, etc) perfunctorily in order to glance at the contents|
|12.||thumb one's nose at to deride or mock, esp by placing the thumb on the nose with fingers extended|
|[Old English thūma; related to Old Saxon thūma, Old High German thūmo, Old Norse thumall thumb of a glove, Latin tumēre to swell]|
The short thick digit of the human hand, next to the index finger and opposable to each of the other four digits.
thumbn. The slider on a window-system scrollbar. So called because moving it allows you to browse through the contents of a text window in a way analogous to thumbing through a book.
short, thick first digit of the human hand and of the lower-primate hand and foot. It differs from other digits in having only two phalanges (tubular bones of the fingers and toes). The thumb also differs in having much freedom of movement and being opposable to tips of other digits. The corresponding first digit (most medial digit) in other vertebrates is also called the thumb, especially if it has some manipulative or special ability (e.g., in the raccoon and the bat)
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