# terminator

/ˈtɝməˌneɪtɝ/ (US) · /tˈɜːmɪnˌeɪtɐ/ (UK)

Source: https://englishreference.com/word/terminator
Updated: 2026-08-27

## Senses

### 1. someone who ends something

noun · CEFR C1 · Formal

a person who brings something to an end or finishes a process.

For teachers: an agent or person who terminates a process, contract, or situation.

- The company hired a terminator to handle the closing of the old factory.
- In corporate restructuring, the consultant acted as a terminator, systematically ending underperforming contracts to save the parent company.

### 2. astronomy

noun · CEFR C2 · Technical

the line on a moon or planet that separates the side in sunlight from the side in darkness.

For teachers: the dividing line between the illuminated and unilluminated parts of a celestial body.

- Through the telescope, you can see craters clearly along the moon's terminator.
- Shadows are longest and most dramatic near the terminator, providing astronomers with the best view of lunar topography.

### 3. computing/electronics

noun · CEFR C1 · Technical

a piece of hardware or a code that marks the end of a data stream.

For teachers: a device or character sequence that signifies the end of a transmission or prevents signal reflection in a circuit.

- The programmer forgot to add a null terminator at the end of the string.
- Without a proper terminator at the end of the SCSI chain, signal reflections can cause significant data corruption.

### 4. science/biology

noun · CEFR C2 · Technical

a specific part of a gene that tells the cell to stop copying DNA.

For teachers: a section of nucleic acid sequence that marks the end of a gene or operon in genomic DNA during transcription.

- The enzyme stops moving once it reaches the terminator sequence on the DNA.
- The researchers identified a rho-independent terminator that effectively halted RNA polymerase activity in the bacterial culture.

### 5. science fiction robot

noun · CEFR B2 · Informal

a powerful robot or android designed to hunt and kill people, usually from movies.

For teachers: a fictional, highly resilient autonomous android designed for assassination or extermination.

- The movie features a terminator sent from the future to change history.
- The cultural image of the terminator has become a standard metaphor for the potential dangers of uncontrolled artificial intelligence.

## Examples

- The moon's craters are most visible along the terminator.
- Astronomers often observe the lunar surface near the terminator because the long shadows reveal the height of mountains.
- As the spacecraft approached the planet, the high-resolution cameras captured the sharp contrast of the terminator, where the harsh sunlight gave way to the deep shadows of the nocturnal hemisphere.

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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.