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 one video, Joseph can be seen lying on his back and wearing a camo onesie. —Hannah Sacks, PEOPLE, 8 Jan. 2026

Only two officers had managed to pull on their protective coveralls, stretchy black suits that look like onesies and shield them from flames and chemical spray. —Jamie Thompson, The Atlantic, 6 Jan. 2026

Hurley spent Christmas this year with boyfriend Billy Ray Cyrus in matching red holiday onesies and festive headbands. —Lara Walsh, InStyle, 29 Dec. 2025

Lopez shared the news with her husband at a Dodgers baseball game in August, handing him a package with a note and a onesie. —Laura Ungar The Associated Press, Arkansas Online, 28 Dec. 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