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

… 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

In the clip, Ciara was seen standing next to four shirts emblazoned with each of her kids’ names as well as a blank baby onesie set aside for her fifth baby. — Escher Walcott, PEOPLE, 8 Sep. 2026

In a short video, the Grammy-winning R&B songstress can be seen hanging four crisp white t-shirts onto a clothesline outside, before adding a tiny baby onesie onto the end of the rope. — Jennifer Hassan, USA Today, 7 Sep. 2026

In the pregnancy announcement, Ciara and Wilson posed outside alongside four shirts hanging on a clothesline with a blank baby onesie representing the newest addition to their family. — ABC News, 6 Sep. 2026

Each drop features a selection of bangers picked by The Drive crew, all available on T-shirts, hoodies, posters, kid shirts, and even baby onesies. — Kyle Cheromcha, The Drive, 19 Aug. 2026

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

• creasy
• fleecy
• greasy