one·​sie | \ ˈwən-zē How to pronounce onesie (audio) \
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 Ellen also gifted the couple with a onesie covered in her face. Billboard Staff, Billboard, "Orlando Bloom Says That Baby Daisy Dove is Half Him, Half Katy Perry: Watch," 7 Oct. 2020 Mikita, 34, shared a photo of a onesie from the Las Vegas hospital where Beckett was born. Ally Mauch,, "Jesse Tyler Ferguson and Justin Mikita Are 'Over the Moon' After Birth of Their First Child," 11 July 2020 This onesie is a perfect pic for beachy photos and summertime picnics. Alexandra Cavallo, USA TODAY, "25 of the cutest baby outfits for summer," 29 June 2020 The child was last seen about 7 p.m. Sunday. Serenity, who is black and has black hair and brown eyes, was wearing a white onesie and diamond stud earrings. Dana Branham, Dallas News, "Amber Alert issued for 7-month-old and her mother last seen in Irving," 8 June 2020 Even if there were dirty dishes in the sink and damp baby onesies in the hamper, the note must go out. Beth Thames |, al, "Note to self: Don’t throw away old letters," 12 May 2020 The stylish youngster strikes an expert pose in the image, wearing a frilly pink bit of tulle around her shoulders that perfectly matches the trim around her sparkly onesie. Jen Juneau,, "Khloé Kardashian's Daughter True, 17 Months, Is Ready for 'Fashion Week' in Chic All-Pink Outfit," 12 Sep. 2019 Rose stuck her fingers in the potatoes and wore a pumpkin onesie that Annie had picked out special. Hilary Leichter, Harper's Magazine, "Terrace Story," 25 May 2020 The family wore animal onesies in some of the photos taken by Rampey. NBC News, "Porch portraits: Families pose during a pandemic," 5 Apr. 2020

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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Time Traveler for onesie

Time Traveler

The first known use of onesie was in 1983

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Last Updated

13 Oct 2020

Cite this Entry

“Onesie.” Dictionary, Merriam-Webster, Accessed 30 Nov. 2020.

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