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onesie

American  
[wuhn-zee] / ˈwʌn zi /

noun

  1. a one-piece leisure or sleeping garment for an adult, usually combining a long-sleeved top with long pants.


Trademark.
  1. Onesies, a brand name for one-piece garments for infants, the lower portion resembling briefs and having snaps across the crotch for convenience in diapering. Although a trademarked term, it is often spelled as lowercase onesie, referring to a single garment.

onesie British  
/ ˈwʌnzɪ /

noun

  1. a one-piece garment combining a top with trousers, worn by adults as leisurewear

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What else does onesie mean? A onesie is a one-piece item of loungewear or sleepwear. Traditionally, onesies are worn by babies, but they exploded into adult novelty fashion in the 2010s.How is onesie pronounced?[wuhn-zee]

Etymology

Origin of onesie

First recorded in 1980–85; originally a trademark

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

As a parent, you wouldn’t want your child to be stuck forever wearing a onesie and drinking from a sippy cup.

From The Wall Street Journal

Dodgers were undefeated when my 6 month old wore a Dodgers onesie, until game 1 of the World Series.

From Los Angeles Times

The 66-pound robot wears a sweater-like onesie, because nothing says “I’m harmless” like cozy knitwear.

From The Wall Street Journal

Emmanuel was last seen wearing a black onesie with a Nike logo.

From Los Angeles Times

The boy was last seen wearing a black onesie, authorities said.

From Los Angeles Times