triplet

American  

[trip-lit] / ˈtrɪp lɪt /

noun

• triplets
  plural

1. one of three children or offspring born at the same birth.

2. triplets, three offspring born at one birth.

3. any group or combination of three.

4. Prosody. three successive verses or lines, especially when rhyming and of the same length; a stanza of three lines.

5. Also called tercet.  Music. a group of three notes to be performed in the time of two ordinary notes of the same kind.

6. an assembled imitation gem with three parts, the center one giving the color, the top and bottom, sometimes genuine, supplying the wearing qualities.

7. Genetics. a sequence of three nucleotides; a codon in messenger RNA and an anticodon in transfer RNA.

8. Optics. a compound lens in which three lenses are combined.

9. triplets, (in some card games) three cards of the same denomination.

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triplet British  

/ ˈtrɪplɪt /

noun

1. a group or set of three similar things

2. one of three offspring born at one birth

3. music a group of three notes played in a time value of two, four, etc

4. chem a state of a molecule or free radical in which there are two unpaired electrons

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Other Word Forms

Noun Inflected Forms

• triplets
  plural

Etymology

Origin of triplet

First recorded in 1650–60; triple + -et

Explanation

When a mammal gives birth to three offspring at the same time, each is a triplet. If you're a triplet, you've got at least two siblings right from the moment you're born. While some triplets are identical (three fetuses from a single egg), it's more likely for triplets to be fraternal (from three separate eggs). In humans, twins are more common than triplets, and multiple births of more than three are even more rare. Triplet can also mean another group of three, like three lines of poetry or three notes of music.

Example Sentences

See Examples For:

triplet triplets

In 2008, one sister triplet was miscarried, while two of her sisters lived "for a significant amount of time", but NUH registered all three babies as miscarriages.

From BBC ● Jul. 18, 2026

He married his college sweetheart, with whom he would have triplet sons, and joined Exxon as a research engineer in Tulsa, Okla., in 1963.

From The Wall Street Journal ● Jun. 10, 2026

In this new design, however, the triplet energy is transferred to the lanthanide ions inside the nanoparticles with more than 98% efficiency.

From Science Daily ● May 18, 2026

In many optical systems, triplet states are considered "dark" because their energy is often lost.

From Science Daily ● May 18, 2026

But by 1965, all of these studies—and especially Nirenberg’s—had successfully mapped every DNA triplet to a corresponding amino acid.

From "The Gene" by Siddhartha Mukherjee

Very rare triplets in Los Angeles came close to breaking a world record.

From MarketWatch ● Sep. 1, 2026

The triplets were conceived naturally, Passi said, which happens in only about about one out of 10,000 pregnancies.

From Los Angeles Times ● Aug. 31, 2026

In Canterbury, Kent, triplets Scarlett, Grace and Tabby Taylor said they were ecstatic for themselves and each other after getting into their first choice universities.

From BBC ● Aug. 13, 2026

They had been born triplets; a third boy had died at nine months old.

From The Wall Street Journal ● Jul. 31, 2026

The triplets also wanted to know how much their coins were worth, and if they could pawn them.

From "Made You Up" by Francesca Zappia

Related Words

• threesome
• trilogy
• triumvirate