onesie

noun

one·​sie ˈwən-zē How to pronounce onesie (audio)
plural onesies
1
: a bodysuit for an infant having a snap closure at the crotch and not covering the legs
… her husband, Prince William, gratefully accepted a onesie labeled "Daddy's Little Co-Pilot" from a well-wisher …Michelle Tauber et al.
2
: a one-piece garment for adults usually with long sleeves and pants and sometimes with a hood
… pole-vaulter Holly Bradshaw wore a onesie rather than a crop top and bikini to win her bronze …Vanessa Friedman

Examples of onesie in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
An odd couple—one a goblin squeezed into an improbable trench-coat onesie, a fedora, and high heels—promenades down a steep incline while other strollers come and go. Jeremy Lybarger, Artforum, 2 June 2026 Shower attendees, including Disick and Chyna's sister Dejah, took pictures in a photo booth, decorated infant onesies and were entertained by a belly dancer. Zoey Lyttle, PEOPLE, 22 May 2026 Photos from the event’s heyday show the Eras Tour frontwoman posing with her ‘squad’ of gal pals in matching American flag onesies, or flashing peace signs in stars-and-stripes bikinis. Bailey Bujnosek, InStyle, 21 May 2026 Guests were instructed to wear animal onesies. ABC News, 19 May 2026 See All Example Sentences for onesie

Word History

Etymology

one entry 1 + -sie (after the trademark Onesies)

First Known Use

1983, in the meaning defined at sense 1

Time Traveler
The first known use of onesie was in 1983

Browse Nearby Words

Cite this Entry

“Onesie.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onesie. Accessed 4 Jun. 2026.

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