onesie

noun

one·​sie ˈwən-zē 

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

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 post included a number of family photos, including several of George in a onesie and a shot of the couple’s 2-year-old daughter Bridget checking out her new little brother. —Christie D’zurilla, Los Angeles Times, 24 Apr. 2025

Others were also impressed with Spencer's efforts in dressing his baby in a pink onesie and adorable headband. —Josh Hammer, MSNBC Newsweek, 22 Apr. 2025

That one also featured Decoy lying with a baby onesie, baby shoes, and a sonogram. —Devonne Goode, Parents, 21 Apr. 2025

The 22-year-old was joined by May at the end of his set, emerging in a sparkling onesie shrouded in a regal fur. —Steven J. Horowitz, Variety, 12 Apr. 2025

Word History

Etymology

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

First Known Use

1983, in the meaning defined at sense 1

Rhymes for onesie

• breezy
• cheesy
• easy
• queasy
• sleazy
• wheezy
• marchese
• speakeasy
• uneasy