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

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

Sterling could be seen snuggling up to her father as Bronze sat on his lap, while Patrick appeared to be tickling Golden, who lay next to mom Brittany in a flamingo print onesie. — Kirsty Hatcher, PEOPLE, 18 Aug. 2026

The line features apparel and accessories for babies, including cardigans, rompers, onesies, and other everyday basics. — Chanel Vargas, InStyle, 9 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

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