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.
Terrence was dressed in a giant yellow onesie—a Pokémon. Danielle Parker, CBS News, 19 June 2026 On Wednesday, June 17, the journalist shared an Instagram post featuring herself in a New York Knicks jersey, cradling her sleeping newborn granddaughter, who was wearing a floral onesie. Clare Fisher, PEOPLE, 18 June 2026 The couple’s 1-year-old daughter, Frances Bean, perched on Love’s hip, outfitted in a pastel onesie. Quinn Moreland, Pitchfork, 14 June 2026 The cooling onesie, which was unveiled at a press event on Sunday, will be worn under the Axiom Extravehicular Mobility Unit (AxEMU) space suit, which is also designed in collaboration with Prada. Claire Cameron, Scientific American, 8 June 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 24 Jun. 2026.

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