# duplicate

/ˈdupɫəˌkeɪt/ (US)

Source: https://englishreference.com/word/duplicate
Updated: 2026-06-20

## Senses

### 1. an identical copy

noun · CEFR B2

an exact copy of something, like a document or a key.

For teachers: an identical copy or counterpart of an original object or document.

- I keep a duplicate of my house key with a neighbor just in case.
- The legal team requested a duplicate of the contract to ensure both parties held identical versions of the agreement.

### 2. legal original

noun · CEFR C1 · Formal · Technical

a second version of a legal paper that is just as official as the first one.

For teachers: a document that is the same as another in all essential particulars and carries the same legal validity as the original.

- The lawyer signed the duplicate so that both offices had a valid copy.
- In property law, a duplicate lease is executed so that the landlord and tenant each possess an original instrument of the agreement.

### 3. to make a copy

verb · CEFR B2

to make an exact copy of something.

For teachers: to produce an exact copy of a physical or digital object. Transitive use requiring a direct object.

- We need to duplicate these files before we start editing them.
- The software allows users to duplicate entire databases with a single command, ensuring data redundancy across multiple servers.

### 4. to repeat an action

verb · CEFR B2

to do something again in the same way.

For teachers: to perform an action or process again, often with the goal of achieving the same result.

- It will be hard to duplicate the success of last year's festival.
- Scientists struggled to duplicate the results of the initial experiment, leading to questions about the original methodology.

### 5. identical

adjective · CEFR B2

exactly the same as another thing.

For teachers: being exactly the same as another; existing as a second version of an original.

- The museum has duplicate copies of several famous ancient coins.
- The investigation revealed that the suspect had been using duplicate license plates to avoid detection by traffic cameras.

## Examples

- I keep a duplicate of my house key in my wallet.
- The lawyer requested a duplicate of the contract because the original was lost in the mail.
- In botanical research, a duplicate is an additional specimen collected from the same plant at the same time as the original type specimen to ensure a record exists in multiple herbaria.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.