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Synonyms

bikini

1 American  
[bih-kee-nee] / bɪˈki ni /

noun

plural

bikinis

  1. a very brief, close-fitting, two-piece bathing suit for women or girls.

  2. a very brief, close-fitting pair of bathing trunks for men or boys.

  3. Often bikinis. underwear briefs that are fitted low on the hip or below it.

Bikini 2 American  
[bih-kee-nee] / bɪˈki ni /

noun

  1. an atoll in the N Pacific, in the Marshall Islands: atomic bomb tests 1946. 3 sq. mi. (8 sq. km).

Bikini 1 British  
/ bɪˈkiːnɪ /

noun

  1. an atoll in the N Pacific; one of the Marshall Islands: site of a US atomic-bomb test in 1946

"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
bikini 2 British  
/ bɪˈkiːnɪ /

noun

  1. a woman's very brief two-piece swimming costume

"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

Etymology

Origin of bikini

1945–50; < French, apparently named after Bikini

Explanation

A bikini is a two-piece women's bathing suit. Bikinis are usually skimpy, and a particularly small one inspired a song from 1960 called "Itsy Bitsy Teeny Weeny Yellow Polka Dot Bikini.” We don't normally associate atomic bomb tests with cute bathing suits, but this one's an exception. The bikini is named after the Pacific atoll of the same name, where an atomic bomb was exploded in 1946. The reason a tiny bathing suit is named after a tiny island isn’t clear. Although a bikini isn't as explosive as a bomb, it is likely to be worn by a bombshell.

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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.

I love the story Didion tells of going to Ralphs in a bikini on a 105-degree day.

From Los Angeles Times • Dec. 4, 2025

I’m standing on a Connecticut beach in a bikini at 6:25 a.m. on a November morning.

From The Wall Street Journal • Nov. 7, 2025

The Era of No Rules came and went so quickly that Susan Collins couldn’t even make good on the bikini trial balloon.

From Slate • Sep. 30, 2023

Sen. Susan Collins, R-Maine, unwittingly insulted herself by threatening to wear a bikini.

From Salon • Sep. 21, 2023

Audrey wore a bikini, Jenna, a sporty black tankini, and I had on an oversize T-shirt over my striped one-piece.

From "Keep It Together, Keiko Carter" by Debbi Michiko Florence

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.