# thumb

/ˈθəm/ (US) · /θˈʌm/ (UK)

Source: https://englishreference.com/word/thumb
Updated: 2026-06-19

## Senses

### 1. the finger

noun · CEFR A2

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

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

- He accidentally hit his thumb with the hammer while fixing the fence.
- The evolution of the opposable thumb is often cited as a critical factor in the development of complex tool use among early hominids.

### 2. Internet/Computing

noun · CEFR B2 · Informal

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

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

- Click on the thumb to see the full-sized photo from the gallery.
- The website's gallery loads low-resolution thumbs initially to ensure the page remains responsive on slower mobile connections.

### 3. to look through a book

verb · CEFR B2

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

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

- I thumbed through the magazine while waiting for my doctor's appointment.
- She thumbed through the heavy manual, searching for the specific diagram that explained the engine's cooling system.

### 4. to hitchhike

verb · CEFR B2 · Informal

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

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

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

## Examples

- He gave a quick thumbs-up to show he was ready.
- She scrolled through the news on her phone using only her thumb while holding a coffee cup.
- The evolution of the opposable thumb is frequently cited as a primary factor in the development of complex tool use among early hominids.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.