detector

noun

de·​tec·​tor di-ˈtek-tər 

: one that detects: such as

a

: a device for detecting the presence of electromagnetic waves or of radioactivity

b

: a rectifier of high-frequency current used especially for extracting the intelligence from a radio signal

Synonyms

• sensor

Examples of detector in a Sentence

using metal detectors to improve safety at airports

a motion detector to thwart burglaries

Recent Examples on the Web

Specifically, the neutrino bumped into some matter and created another type of tiny particle called a muon, which in turn set off a glowing wave of blue photons that the detector could see. —Sara Hashemi, Smithsonian Magazine, 14 Feb. 2025

The vacuum also has a Cliff Detect feature that prevents it from falling down stairs and a dirt detector to identify spots that need a deeper clean. —Lauren Taylor, Better Homes & Gardens, 14 Feb. 2025

The new telescope's infrared detectors have to be kept super cold, so the instrument is housed inside three concentric cones atop a set of mirrors that protect it from the Sun's energy and the spacecraft's own heat. —Ari Daniel, NPR, 9 Feb. 2025

The system boasted heat and flame detectors, fire retardant, a 2,500-gallon sprinkler system to soak the property and humidify the air for an hour, and autonomy from the power grid. —Alex Wigglesworth, Los Angeles Times, 17 Jan. 2025

Word History

First Known Use

1541, in the meaning defined above

Phrases Containing detector

• lie detector
• metal detector
• radar detector
• smoke detector

Kids Definition

detector

noun

de·​tec·​tor di-ˈtek-tər 

1

: one that detects or warns

a smoke detector

2

: a device in a radio receiver for changing the high-frequency current of radio waves into current that can vibrate a loudspeaker to reproduce the original sound

Medical Definition

detector

noun

de·​tec·​tor di-ˈtek-tər 

: one that detects

especially : a device for detecting the presence of electromagnetic waves or of radioactivity