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thumb

n. · v.
US //ˈθəm// UK //θˈʌm// thumb
  1. 1 the finger (n.)
    A2 Elementary

    the short, thick finger on the side of your hand that can touch your other fingers.

    the first and thickest digit of the human hand, characterized by its opposability to the other four fingers.

    Example

    He accidentally hit his thumb with the hammer while fixing the fence.

    Example

    The evolution of the opposable thumb is often cited as a critical factor in the development of complex tool use among early hominids.
  2. 2 Internet/Computing (n.)
    B2 Upper Intermediate Informal Computing

    a small version of a larger image on a computer or phone.

    a reduced-size version of a digital image or video, used for indexing or previewing.

    Example

    Click on the thumb to see the full-sized photo from the gallery.

    Example

    The website's gallery loads low-resolution thumbs initially to ensure the page remains responsive on slower mobile connections.
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  1. 3 to look through a book (v.)
    B2 Upper Intermediate

    to turn the pages of a book or magazine quickly without reading everything.

    to turn pages rapidly with the thumb, typically for a cursory or superficial examination of the content.

    Example

    I thumbed through the magazine while waiting for my doctor's appointment.

    Example

    She thumbed through the heavy manual, searching for the specific diagram that explained the engine's cooling system.
  2. 4 to hitchhike (v.)
    B2 Upper Intermediate Informal travel

    to try to get a free ride from a passing car by holding out your thumb.

    to solicit a free ride from a passing vehicle by gesturing with the thumb.

    Example

    We managed to thumb a ride to the next town after our car broke down.

    Example

    In the early seventies, it was quite common for students to thumb their way across the continent during the summer holidays.

    Usage

    often used in the phrase 'thumb a lift' or 'thumb a ride'
Origin

Derived from Middle English thombe, thoume, thoumbe (“thumb”), from Old English þūma (“thumb”), from Proto-West Germanic þūmō (“thumb”), from Proto-Germanic þūmô (“thumb”), from Proto-Indo-European *tūm- (“to grow”). Cognate with West Frisian tomme (“thumb”), Dutch duim (“thumb”), Low German Duum (“thumb”), German Daumen (“thumb”), Danish and Norwegian tomme (“inch”), Norn tum (“thumb”), Swedish tumme (“thumb”), tum (“inch”), Ancient Greek τύμβος (túmbos, “burial mound”). Also compare Welsh tyfu (“to grow”), Latin tumēre (“to swell”), Lithuanian tumėti (“to thicken, clot”), Avestan 𐬀𐬨𐬏𐬙 (amūt, “strong”), Sanskrit तुम्र (túmra, “strong, thick”). The parasitic ‐b has existed since the late 13th century. Doublet of tomb.

Idioms7 entries

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