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pacifier

American  
[pas-uh-fahy-er] / ˈpæs əˌfaɪ ər /

noun

  1. a person or thing that pacifies.

  2. a rubber or plastic device, often shaped into a nipple, for a baby to suck or bite on.


pacifier British  
/ ˈpæsɪˌfaɪə /

noun

  1. a person or thing that pacifies

  2. a baby's dummy or teething ring

"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 pacifier

First recorded in 1525–35; pacify + -er 1

Explanation

A pacifier is a soothing device for babies that's made of rubber, silicone, or plastic. If you can picture the cartoon character Maggie Simpson, then you can picture a pacifier. Most infants are born with a strong need to suck, and many of them suck their own thumbs or fingers to soothe themselves. A pacifier works the same way. While some parents and even doctors worry that continuing to use pacifiers too long can damage babies' developing teeth and palates, such problems are actually very rare. The original meaning of pacifier is "anything (or anyone) that pacifies," from the Latin pacificare, "make peace; calm."

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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.

“Was just reading today that newborns will suck on a pacifier more vigorously if it triggers playback of a recording of her/his mother’s voice than another woman’s voice,” Tramo wrote to Epstein.

From Los Angeles Times • Feb. 12, 2026

The software records data as an infant sucks on the pacifier and compares that data with information from other infants.

From Science Daily • Apr. 29, 2024

About a third of the kiddos in most classes at the two Seattle area high schools where I teach have just checked out and use them as a pacifier.

From Seattle Times • May 12, 2023

She called herself a "human pacifier" and reluctantly started co-sleeping before realizing she needed to make changes before going back to work.

From Salon • May 12, 2023

When a mother—harried, in heels—clip-clopped past her, Madeline Ryan scooped up a pacifier thrown out of the stroller and raced after them to hand it over.

From "Little Fires Everywhere" by Celeste Ng