bikini

noun

bi·​ki·​ni bə-ˈkē-nē 

plural bikinis

1

a

: a two-piece bathing suit worn by women that does not cover the midriff see also string bikini, tankini

b

: a short snug swimsuit worn by men

2

: a pair of low-cut briefs (see brief entry 2 sense 4)

Launched in May, the underwear brand for men and women includes bikinis, … G-strings and boxer briefs.

—Phyllis Furman

… ultra low-rise jeans with a built-in bikini or thong.

—Sunday Tribune (South Africa)

—often used before another noun

Bikini briefs are usually lower than the true waist, often at the hips.

—Clifford Pugh

bikinied adjective

or less commonly bikini'd

bə-ˈkē-nēd 

Did you know?

In July 1946, a US Army–Navy task force detonated two thermonuclear bombs at Bikini, an atoll in the Marshall Islands in the Pacific Ocean, and the event dominated news around the world. A French designer, Jacques Heim, used the occasion to introduce a skimpy two-piece bathing suit dubbed l’atome, “the atom.” Another designer, Louis Réard, followed it up with an even smaller suit for which he registered the name bikini. It was first modeled by dancer Micheline Bernardini at a Paris fashion show on July 5. There is no solid evidence for why he gave this name to the suit, but it has since become an international word.

Examples of bikini in a Sentence

Recent Examples on the Web

Aniston opted for a brown bikini top, pink bikini bottoms and sunglasses. — Angelique Brenes, PEOPLE, 30 July 2026

Meanwhile, Rodríguez could be seen swimming behind him, wearing a plunging black bikini top paired with cheeky black thong bottoms. — Hannah Malach, InStyle, 30 July 2026

In its complaint, xAI seems to tiptoe around mentions of bikinis, after much of the Grok backlash following an X post Musk made that advertised Grok’s ability to put anyone in a bikini. — Ashley Belanger, ArsTechnica, 29 July 2026

Even more mind-boggling is the fact that Will went to bed without saying good night to Suzanne, who was in her bikini, getting ready to hot tub with another man. — Rafaela Bassili, Vulture, 28 July 2026

Word History

Etymology

French, from Bikini, atoll of the Marshall Islands

First Known Use

1947, in the meaning defined at sense 1a

Phrases Containing bikini

• bikini wax
• string bikini

Rhymes for bikini

• acini
• aldine
• amine
• arsine
• carinii
• cosine
• delphine
• domine
• latine
• ovine
• pennine
• porcine

Kids Definition

bikini

noun

bi·​ki·​ni bə-ˈkē-nē 

: a scanty two-piece bathing suit for a girl or woman

Etymology

from French bikini "two-piece bathing suit," from Bikini, atoll in the Marshall Islands

Geographical Definition

Bikini

geographical name

Bi·​ki·​ni bi-ˈkē-nē 

island (atoll) of the Marshall Islands

Note: Bikini was the site of U.S. atomic bomb tests in 1946 and hydrogen bomb tests in 1954 and 1956.

Bikinian

bi-ˈkē-nē-ən 

noun