# detector

/dɪˈtɛktɝ/ (US) · /dɪtˈɛktɐ/ (UK)

Source: https://englishreference.com/word/detector
Updated: 2026-06-20

## Senses

### 1. safety or security device

noun · CEFR B1

a device that finds something hidden or dangerous and often makes a sound to warn you.

For teachers: an instrument designed to sense and signal the presence of a specific physical stimulus, such as smoke, heat, or radiation.

- The smoke detector started beeping because I burnt the toast.
- The building's fire safety system includes a sensitive smoke detector in every hallway to ensure rapid evacuation in an emergency.

Usage: often used in compound nouns like 'smoke detector' or 'metal detector'.

### 2. signal receiver

noun · CEFR C1 · Technical

a part of a radio or electronic machine that picks up a signal and changes it into sound or information.

For teachers: a circuit or component in a receiver that extracts information from a modulated carrier wave.

- The radio uses a small detector to turn the signal into music.
- In early wireless telegraphy, the coherer served as a primitive detector of radio waves before more reliable vacuum tubes were developed.

Usage: typically used in the context of electronics, physics, or telecommunications.

## Examples

- The smoke detector started beeping while I was cooking.
- Security guards at the airport use a metal detector to check passengers for prohibited items before they board.
- Modern research facilities utilize a highly sensitive particle detector to observe subatomic interactions that are otherwise invisible to the naked eye.

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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.