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noun \ˈthəm\

Simple Definition of thumb

  • : the short, thick finger on the side of your hand

  • : the part of a glove or mitten that covers a thumb

Full Definition of thumb

  1. 1 :  the short thick digit of the human hand that is analogous in position to the big toe and differs from the other fingers in having only two phalanges, allowing greater freedom of movement, and being opposable to each of them; also :  a corresponding digit in lower animals

  2. 2 :  the part of a glove or mitten that covers the thumb

  3. 3 :  a convex molding :  ovolo

all thumbs
  1. :  extremely awkward or clumsy

under one's thumb or under the thumb
  1. :  under control :  in a state of subservience <her father did not have her that much under his thumb — Hamilton Basso>

Examples of thumb

  1. a little girl sucking her thumb

  2. I accidentally cut my thumb.

  3. My mitten has a hole in the thumb.

Origin of thumb

Middle English thoume, thoumbe, from Old English thūma; akin to Old High German thūmo thumb, Latin tumēre to swell

First Known Use: before 12th century

Rhymes with thumb




Simple Definition of thumb

  • : to ask for or get a ride in a passing vehicle by sticking out your arm with your thumb up as you stand on the side of the road

Full Definition of thumb

  • transitive verb
    1. 1a :  to leaf through (pages) with the thumb :  turnb :  to soil or wear by or as if by repeated thumbing <a badly thumbed book>

    2. 2 :  to request or obtain (a ride) in a passing automobile by signaling with the thumb

    3. intransitive verb
    4. 1 :  to turn over pages <thumb through a book>

    5. 2 :  to travel by thumbing rides :  hitchhike <thumbed across the country>

    thumb one's nose
    1. 1 :  to place the thumb at one's nose and extend the fingers as a gesture of scorn or defiance

    2. 2 :  to express disdain or defiance <thumb their nose at opulence — Sales Management>

    Examples of thumb

    1. I thumbed a ride to school.

    2. He thumbed his way to New York.

    3. He thumbed across the country.

    Circa 1647

    First Known Use of thumb

    circa 1647

    Medical Dictionary


    noun \ˈthəm\

    Medical Definition of thumb

    1. :  the short and thick first or most preaxial digit of the human hand that differs from the other fingers in having only two phalanges, in having greater freedom of movement, and in being opposable to the other fingers

    Illustration of thumb

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