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 snap, their bundle of joy is wearing a pale pink onesie with angel wings stitched on and a white hat decorated with butterflies. — Giovana Gelhoren, InStyle, 5 Aug. 2026

The British royal family’s official social media pages announced the news the day after the baby’s birth, sharing a photo of the little girl wearing a pink onesie featuring wings on the back and a hat, which was taken by her father. — Stephanie Petit, PEOPLE, 4 Aug. 2026

The snapshot was taken by Brooksbank, according to the royal family, and shows the newborn wearing a pink onesie with wings on the back, as well as a matching hat. — ABC News, 4 Aug. 2026

Eugenie, 36, also confirmed the news in a post on her official Instagram page, which featured a photo of the newborn cuddled up in a pink onesie with angel wings holding onto someone's finger. — Liza Esquibias, USA Today, 4 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