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Synonyms

sniffer

American  
[snif-er] / ˈsnɪf ər /

noun

  1. a person or thing that sniffs.

  2. a device or mechanism for detecting something.

ˈsniffer British  
/ ˈsnɪfə /

noun

  1. a device for detecting hidden substances such as drugs or explosives, esp by their odour

  2. a computer program or device used to monitor, detect, and capture data on a network

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of sniffer

First recorded in 1860–65; sniff + -er 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The sources said the tool, called a "signal sniffer", was mounted on a helicopter.

From BBC • Feb. 18, 2026

The sources said the tool, called a "signal sniffer", was mounted on a helicopter to fly over an area where officials believe she might be, to track down her exact location.

From BBC • Feb. 17, 2026

Footage from the campsite on Mount Maunganui, an extinct volcano, shows a huge slip near the base of the volcanic dome, as rescuers and sniffer dogs comb through crushed caravans and flattened tents.

From BBC • Jan. 22, 2026

Federal prosecutors said they were taken into custody after a judge ordered searches of their homes in the city by police officers backed by explosive sniffer dogs.

From BBC • Oct. 10, 2025

Her ashen hair sits in a quivering pile atop her head and her spectacles, if not teetering on the end of her sniffer, hang from a sterling chain to rest upon her ample bosom.

From "The Bletchley Riddle" by Ruta Sepetys and Steve Sheinkin

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.