# nocturnal

/nɑkˈtɝnəɫ/ (US) · /nɒktˈɜːnəl/ (UK)

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

## Senses

### 1. active at night

adjective · CEFR B2

describes animals or people that are awake and active at night instead of during the day.

For teachers: relating to or characteristic of animals that are active during the night and sleep during the day.

- Owls are nocturnal hunters that use their excellent hearing to find food in the dark.
- Many desert mammals have evolved nocturnal habits to avoid the intense heat of the midday sun.

### 2. happening at night

adjective · CEFR C1 · Formal

happening or done during the night.

For teachers: occurring, done, or active at night; often used in formal or technical descriptions of events.

- The city was quiet except for the occasional nocturnal sounds of traffic.
- The poet was inspired by the nocturnal silence of the countryside, which stood in stark contrast to the chaos of London.

### 3. night-time device

noun · CEFR C2 · Archaic · Technical

an old tool used in the past to tell the time at night by looking at the stars.

For teachers: an instrument formerly used for determining the time of night by the positions of certain stars.

- The museum has a brass nocturnal used by sailors in the seventeenth century.
- Before the invention of reliable mechanical clocks, the nocturnal provided navigators with a means to determine the time using the North Star.

## Examples

- Owls are nocturnal birds that hunt at night.
- The zoo's nocturnal house allows visitors to observe animals that would normally be asleep during the day.
- The city took on a different character after midnight, filled with the nocturnal sounds of distant sirens and the low hum of late-night delivery trucks.

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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.