# pulsar

/ˈpʊɫsɝ/ (US) · /pˈʌlsɑː/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/pulsar
Updated: 2026-05-31

## Definition

a very dense, spinning star that sends out regular bursts of radio waves. These bursts are so steady that they sound like a heartbeat to scientists.

For teachers: a highly magnetised, rotating neutron star that emits beams of electromagnetic radiation. The observed pulses are the result of the star's rotation and the alignment of its magnetic axis with its rotational axis.

## Examples

- Astronomers discovered a new pulsar in the Milky Way.
- Because a pulsar rotates at a constant speed, it serves as a highly accurate cosmic clock for researchers.
- The discovery of the first pulsar in 1967 initially led scientists to speculate about the possibility of an extraterrestrial signal, though it was eventually identified as a rapidly spinning neutron star.

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