duplicate

UK: noun: /ˈdjuːplɪkət/, adjective: /ˈdjuːplɪkət/, verb: /ˈdjuːplɪkeɪt/

US: /n., adj. ˈduplɪkɪt, ˈdju-; v. -ˌkeɪt/

US: (n., adj. do̅o̅′pli kit, dyo̅o̅′-; v. do̅o̅′pli kāt′, dyo̅o̅′-)

Inflections of 'duplicate' (v): (⇒ conjugate)

duplicates

v 3rd person singular

duplicating

v pres p

duplicated

v past

duplicated

v past p

WordReference Random House Learner's Dictionary of American English © 2025

du•pli•cate /n., adj. ˈduplɪkɪt, ˈdyu-; v. -ˌkeɪt/   n., v., -cat•ed, -cat•ing, adj. 
n. [countable]

1. an exact copy:
   He made a duplicate and handed me the original.

v. [~ + object]

2. to make an exact copy of:
   She duplicated a few copies of my letter and handed me the original.
3. to do or perform again;
   repeat:
   You'll just have to duplicate your performance.

adj. [before a noun]

4. exactly like or corresponding to something else:
   a duplicate key.

Idioms

5. Idioms in duplicate, in two identical copies:
   I'll need your letter, in duplicate, on my desk by morning.

du•pli•ca•tion /ˌduplɪˈkeɪʃən, ˌdyu-/  n. 

[uncountable] illegal duplication of material.

See -du-, -plic-.

WordReference Random House Unabridged Dictionary of American English © 2025

du•pli•cate  (n., adj. do̅o̅′pli kit, dyo̅o̅′-;v. do̅o̅′pli kāt′, dyo̅o̅′-), n., v., -cat•ed, -cat•ing, adj. 
n. 

1. a copy exactly like an original.
2. anything corresponding in all respects to something else.
3. Games [Cards.] a duplicate game.
4. Idioms in duplicate, in two copies, esp. two identical copies:
   Please type the letter in duplicate.

v.t. 

5. to make an exact copy of.
6. to do or perform again;
   repeat:
   He duplicated his father's way of standing with his hands in his pockets.
7. to double;
   make twofold.

v.i. 

8. to become duplicate.

adj. 

9. exactly like or corresponding to something else:
   duplicate copies of a letter.
10. consisting of or existing in two identical or corresponding parts;
    double.
11. Games [Cards.] noting a game in which each team plays a series of identical hands, the winner being the team making the best total score.

• Latin duplicātus (past participle of duplicāre to make double), equivalent. to duplic- (stem of duplex) duplex + -ātus -ate¹
• late Middle English 1400–50

du′pli•ca′tive, adj. 
Synonyms

• 1. facsimile, replica, reproduction.
• 5. See imitate. 
• 10. twofold.

Antonyms

• 1. original.

Collins Concise English Dictionary © HarperCollins Publishers::

duplicate adjective / ˈdjuːplɪkɪt/

1. copied exactly from an original
2. identical
3. existing as a pair or in pairs; twofold

noun / ˈdjuːplɪkɪt/

1. an exact copy; double
2. something additional or supplementary of the same kind
3. two exact copies (esp in the phrase in duplicate)

verb / ˈdjuːplɪˌkeɪt/

1. (transitive) to make a replica of
2. (transitive) to do or make again
3. (transitive) to make in a pair; make double

Etymology: 15th Century: from Latin duplicāre to double, from duo two + plicāre to fold

duplicable / ˈdjuːplɪkəb^əl/ adjective