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

The baby was last seen wearing a light blue onesie with dots and a white rabbit on the left leg and a headband to match, according to WRAL-TV. Ryan Gaydos, Fox News, "Amber Alert issued after registered sex offender takes 7-month-old from mother in Virginia, police say," 4 June 2018 With the majority of the box now free, Rasco loaded it with onesies, diapers, doggie bags for dirty diapers and a disposable changing table. Sarah Schreiber, Good Housekeeping, "Parents Everywhere Are Obsessed With This Mom's Genius Diaper Bag Trick," 17 Apr. 2017 In March 2018, Perry wore a onesie covered with pictures of Orlando Bloom's face, which seemed to be a pretty clear sign that the relationship was back on. Amy Mackelden, Harper's BAZAAR, "Katy Perry and Orlando Bloom Met the Pope on Their Latest Date," 28 Apr. 2018 Earlier in April, Isidora also shared a group photo that featured her, Shailene, Ben, and two other friends hanging out in onesies. Kara Nesvig, Teen Vogue, "Shailene Woodley's Date Night Photo with Isidora Goreshter Had Some Fans Asking Questions," 27 Apr. 2018 Among the items: a Nazi swastika pendant, and a hangman’s noose decal, a cross burning baby onesie. Frank Witsil, Detroit Free Press, "Amazon blasted for offering merchandise promoting white supremacy," 6 July 2018 The shirts that come in several shades, plus similar baby onesies and even frisbees, spurred a grassroots call to boycott the world's biggest retailer., "Wal-Mart draws fire for 'Impeach 45' T-shirts," 3 July 2018 Could the baby wear a onesie from the Senate gift shop that says Future Senator? Bridget Read, Vogue, "All of the Insane Questions Male Senators Asked About Tammy Duckworth’s Proposal to Allow Infants on the Senate Floor," 18 Apr. 2018 Arguably the most disturbing products included a baby onesie featuring a burning cross – a terroristic symbol of the Ku Klux Klan – and a children’s backpack featuring a cartoon frog wearing a Nazi SS officer’s cap. David Z. Morris, Fortune, "Amazon Sold Books, Backpacks, and Toys Promoting Hate to Kids, Report Shows," 7 July 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

4 Sep 2018

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Time Traveler for onesie

The first known use of onesie was in 1983

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What made you want to look up onesie? Please tell us where you read or heard it (including the quote, if possible).


exaggeratedly or childishly emotional

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