one·​sie | \ ˈwən-zē \
plural onesies

Definition of onesie 

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 All eyes were on Pharrell Williams' wife, Helen Lasichanh, during the Met Gala on May 1, but it was for all the wrong reasons. We were hoping Helen would show off her amazing post-baby body after birthing triplets, but instead, she covered her body in a giant red onesie that some Twitter users were comparing to the red Teletubbie!— Christopher Rogers

Examples of onesie in a Sentence

Recent Examples on the Web

In short, Camila on Wednesday night was perfectly rocking both sides of our holiday season persona: the party-ready, sequin-clad fashionista…and the Netflix-watching, onesie-wearing lounger. Avery Matera, Teen Vogue, "Camila Cabello Wore Butt Flap Pajamas on the Red Carpet," 6 Dec. 2018 The full line contains a hoodie, long-sleeve shirts, cups, a journal, and even baby onesies. Marina Liao, Marie Claire, "Michelle Obama Releases a Merch Line in Honor of Her Book 'Becoming'," 14 Nov. 2018 Millie and Maddie rocked onesies for the big number, while Lilia kept things comfortable in PJs and a simple Coke t-shirt. Tamara Fuentes, Seventeen, "Millie Bobby Brown, Maddie Ziegler, and Lilia Buckingham Just Posted the Best Spice Girls Cover Ever," 6 Nov. 2018 However, Stormi did her part to promote her daddy's new album by wearing an Astroworld onesie. Isabel Greenberg, Harper's BAZAAR, "Kylie Jenner Goes Bare and Literally Glows in Travis Scott's New Music Video," 7 Aug. 2018 Some of his listeners sent onesies to the station and one included a little pacifier with a mustache. Chicago Tribune,, "Algren Award finalist: "Nothing Less Than 20,000 Watts" by Susan Finch," 2 June 2018 Stormi dressed in a pink silk onesie and had her hair tied into a tiny bun with a butterfly clipped in, and a pair of mini wings to match her mama. Isabel Greenberg, Harper's BAZAAR, "Kylie Jenner and Stormi Webster Twinned as Pink Butterflies for Halloween," 30 Oct. 2018 Check out his dramatic entrance here (sorry, no audio): Turner, for her part, went as an elephant in a comfy onesie. Krystin Arneson, Glamour, "Joe Jonas Dressed Up as Fiancée Sophie Turner's Game of Thrones Character for Halloween," 28 Oct. 2018 Also for sale are $250 toy versions of the Model S, $25 infant onesies, and a $35 Starman mug. Elizabeth Lopatto, The Verge, "Elon Musk’s Teslaquila is actually a good idea," 19 Oct. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'onesie.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of onesie

1983, in the meaning defined at sense 1

History and Etymology for onesie

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

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Statistics for onesie

Last Updated

9 Jan 2019

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Time Traveler for onesie

The first known use of onesie was in 1983

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