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Synonyms

duplicate

American  
[doo-pli-kit, dyoo-, doo-pli-keyt, dyoo-] / ˈdu plɪ kɪt, ˈdju-, ˈdu plɪˌkeɪt, ˈdju- /

noun

  • duplicates
    plural
  1. a copy exactly like an original.

    Synonyms:
    reproduction, replica, facsimile
    Antonyms:
    original
  2. anything corresponding in all respects to something else.

  3. Cards. a duplicate game.


verb (used with object)

  • duplicates,
    present (3rd person singular)
  • duplicated,
    past participle,  past
  • duplicating
    present participle
  1. to make an exact copy of.

  2. to do or perform again; repeat.

    He duplicated his father's way of standing with his hands in his pockets.

  3. to double; make twofold.

verb (used without object)

  • duplicates,
    present (3rd person singular)
  • duplicated,
    past participle,  past
  • duplicating
    present participle
  1. to become duplicate.

adjective

  1. exactly like or corresponding to something else.

    duplicate copies of a letter.

  2. consisting of or existing in two identical or corresponding parts; double.

    Synonyms:
    twofold
  3. Cards. noting a game in which each team plays a series of identical hands, the winner being the team making the best total score.

idioms

  1. in duplicate, in two copies, especially two identical copies.

    Please type the letter in duplicate.

duplicate British  
/ ˈdjuːplɪkəbəl /

adjective

  1. copied exactly from an original

  2. identical

  3. existing as a pair or in pairs; twofold

"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

noun

  1. an exact copy; double

  2. something additional or supplementary of the same kind

  3. two exact copies (esp in the phrase in duplicate )

"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

verb

  1. (tr) to make a replica of

  2. (tr) to do or make again

  3. (tr) to make in a pair; make double

  4. (intr) biology to reproduce by dividing into two identical parts

    the chromosomes duplicated in mitosis

"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

Synonym Usage

See imitate.

Other Word Forms

Derived Forms

Inflected Forms

Nouns

Participles

Conjugated Forms

Present

Past

Future

Etymology

Origin of duplicate

First recorded in 1400–50; late Middle English, from Latin duplicātus (past participle of duplicāre “to make double”), equivalent to duplic- (stem of duplex ) duplex + -ātus -ate 1

Explanation

Duplicate describes something that's an exact copy. If you tend to accidentally lock yourself out of your car, it's a good idea to carry a duplicate key with you just in case. The word duplicate is useful when you're talking about a copy of something, like a duplicate of your birth certificate that you keep in a file, or a duplicate driver's license that you apply for after losing the original one. The verb duplicate is pronounced differently, with a long a sound, and it means to make a copy of or to multiply times two. The Latin root, duplicatus, means "to double."

Keep Reading on Vocabulary.com

Vocabulary lists containing duplicate

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.

See Examples For:

U2 has said that both of the shorter releases stand alone, and will not duplicate songs from the eventual full-length set.

From The Wall Street Journal Sep. 9, 2026

The bill may also contain coding errors, duplicate charges or costs that should have been covered.

From MarketWatch Jul. 28, 2026

I’d like to congratulate Mel Brooks on making it to the age of 100, but I’m not sure I want to duplicate his achievement.

From Los Angeles Times Jul. 1, 2026

"It's focused too much on whether silicon can duplicate a human brain and not enough on the broader question of what kinds of systems can be conscious," he said.

From Science Daily Jun. 24, 2026

Her face is an almond sheen of sweat under her white cotton turban, and her lace blouson, settled off her shoulders, reveals duplicate moles, big and black as beetles, at the base of her throat.

From "Dreaming in Cuban" by Cristina García

After removing duplicates of stocks in two or more of the groups, our initial list was made up of 523 stocks.

From MarketWatch Jul. 17, 2026

The posts have no direct connection to Rare Beauty, according to a spokeswoman, who said the brand doesn’t work with AI-generated creators or duplicates.

From The Wall Street Journal Jul. 15, 2026

A search for his surname on the DOJ website returns over 2,000 results, though many of those are duplicates, and Elkholy said the files show he only met Epstein 10-12 times over a 10-year period.

From BBC Mar. 27, 2026

Miguel Sangalang, director of the Bureau of Street Lighting, said there are 33,000 open service requests to fix streetlights across L.A., although some may be duplicates.

From Los Angeles Times Feb. 14, 2026

Instantly there were some heavy tablets in it, signed by Aristotle, a parchment signed by Hecate, and some type-written duplicates signed by the Master of Trinity, who could not remember having met him.

From "The Once and Future King" by T. H. White

Across volatile regions, some critical infrastructure, like desalination plants and data centers, will need to be fortified with layers of reinforced concrete, duplicated to provide backups or potentially relocated underground—at significant cost.

From The Wall Street Journal Jul. 4, 2026

Beyond these broad patterns lies enormous individual variation: blood vessels may follow different routes, muscles may be absent or duplicated, and even the folding patterns of the brain differ from person to person.

From Science Daily Jun. 21, 2026

Its elements have been duplicated, sampled and reimagined so many times that it now exists in countless forms, offering endless ways in.

From Los Angeles Times May 19, 2026

Nevertheless, some of the works involved are "especially popular and duplicated many times online", making it difficult to exclude them completely from training data.

From Barron's Mar. 20, 2026

“He duplicated yours. Hugo, when you do a cartwheel, keep your body straighter and aligned on a single plane, like a wheel turning. Hugo, do a cartwheel!”

From "Fablehaven" by Brandon Mull

Countries seeking to protect domestic companies are also duplicating efforts, such as building too many different types of armored vehicles.

From The Wall Street Journal Jul. 5, 2026

Instead, it can draw on existing mental components, recombine them, and avoid duplicating work, a strategy that current AI systems generally lack.

From Science Daily Nov. 28, 2025

Guthy had made a living duplicating audiocassettes for medical conferences and real estate professionals selling home study programs who would then turn around and sell them to customers for hundreds of dollars on infomercials.

From Slate Feb. 21, 2025

The commission says the US company whose system it used maintained that "duplicating a voter on the voter list is impossible, as each voter is registered only once".

From BBC Oct. 29, 2024

Sophie grabbed a leaflet and noted that it had been produced on a duplicating machine.

From "Hitler Youth: Growing Up in Hitler's Shadow" by Susan Campbell Bartoletti

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