pulsar

noun

pul·​sar ˈpəl-ˌsär 

: a celestial source of pulsating electromagnetic radiation (such as radio waves) characterized by a short relatively constant interval (such as .033 second) between pulses that is held to be a rotating neutron star

Examples of pulsar in a Sentence

Recent Examples on the Web

With the pulsar effectively invisible, the planet’s faint glow could be studied in remarkable detail. —Neetika Walter, Interesting Engineering, 16 Dec. 2025

The first planets beyond the solar system ever confirmed, Poltergeist (PSR B1257+12 B) and Phobetor (PSR B1257+12 C), spotted in 1992, also orbit pulsars, a young, rapidly spinning form of neutron star. —Robert Lea, Space.com, 16 Dec. 2025

After the detection of hydrogen, astronomers discovered previously unknown types of stars, such as pulsars and quasars. —Gabriela Radulescu, The Conversation, 4 Nov. 2025

This observation seemed to support the pulsar theory, with experts theorizing that the glow would have taken a more spherical form if its source were dark matter. —Jacopo Prisco, CNN Money, 20 Oct. 2025

Word History

Etymology

puls(ating) + -ar (in quasar)

Note: The coinage was apparently made by the astronomers Jocelyn Bell Burnell (born 1943 in Northern Ireland) and Antony Hewish (born 1924 in England), who discovered the objects in November, 1967. The Oxford English Dictionary, 3rd edition, cites the following from the Daily Telegraph (March 5, 1968, p. 21): "The name Pulsar (Pulsating Star) is likely to be given to it … Dr. A. Hewish … told me yesterday: '…I am sure that today every radio telescope is looking at the Pulsars.'" The word pulsar was not used in the first formal report of the discovery (A. Hewish, S.J. Bell, et al., "Observation of a Rapidly Pulsating Radio Source," Nature, vol. 217, February 24, 1968, pp. 709-13).

First Known Use

1968, in the meaning defined above