pro·​to·​star ˈprō-tō-ˌstär How to pronounce protostar (audio)
: a cloud of gas and dust in space believed to develop into a star

Examples of protostar in a Sentence

Recent Examples on the Web Other outflows are also seen in this image, including one from the protostar in the top of the image, with its illuminated cavity walls. Eric Berger, Ars Technica, 6 Dec. 2023 The protostar itself sits in the rotating, dusty disk at the center of the image, where infrared radiation cannot escape because of the density of the dust and gas. Lori Youmshajekian, Scientific American, 14 Dec. 2023 As the material from the disk accretes onto the protostar, the protostar gets hotter. Phil Plait, Discover Magazine, 2 July 2010 The nebula contains a shockingly large protostar that is, astronomers estimate, some 300 times larger than our Solar System and has a mass of 2,000 Suns. Eric Berger, Ars Technica, 11 Jan. 2024 Their hearts hold the keys to understanding a range of stellar bodies, from fledgling protostars to zombie white dwarfs, because deep within them lies an invisible force that can shape a star’s destiny: the magnetic field. WIRED, 26 Nov. 2023 The bright patches and filaments mark areas with abundant numbers of protostars. Eric Berger, Ars Technica, 23 Oct. 2023 The bright patches and filaments denote areas with large numbers of protostars. Laura Baisas, Popular Science, 11 Oct. 2023 The telescope recently captured an image of a protostar, dubbed HH 211, located 1,000 light-years away. Michael Kan, PCMAG, 14 Sep. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'protostar.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1947, in the meaning defined above

Time Traveler
The first known use of protostar was in 1947

Dictionary Entries Near protostar

Cite this Entry

“Protostar.” Dictionary, Merriam-Webster, Accessed 26 Feb. 2024.

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