protostar
noun
pro·to·star
ˈprō-tō-ˌstär 
: a cloud of gas and dust in space believed to develop into a star
Examples of protostar in a Sentence
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Lee, Johnstone, and their colleagues estimate the protostar may remain surrounded by its dust cloud for another 100,000 years.
—
Andrew Paul, Popular Science, 22 Jan. 2026
This particular outflow is also the longest outflow from a forming star or protostar ever seen by astronomers, stretching out for a staggering 32 light-years.
—Robert Lea, Space.com, 18 Jan. 2026
The central young star, or protostar, weighing as much as 10 of our suns, is located 15,000 light-years away in the outer reaches of our galaxy.
—Eric Lagatta, USA Today, 12 Sep. 2025
The protostar itself is extraordinary.
—Rupendra Brahambhatt, Interesting Engineering, 7 Sep. 2025
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Andrew Paul, Popular Science, 22 Jan. 2026
This particular outflow is also the longest outflow from a forming star or protostar ever seen by astronomers, stretching out for a staggering 32 light-years.
—Robert Lea, Space.com, 18 Jan. 2026
The central young star, or protostar, weighing as much as 10 of our suns, is located 15,000 light-years away in the outer reaches of our galaxy.
—Eric Lagatta, USA Today, 12 Sep. 2025
The protostar itself is extraordinary.
—Rupendra Brahambhatt, Interesting Engineering, 7 Sep. 2025
See All Example Sentences for protostar
Cite this Entry
“Protostar.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/protostar. Accessed 1 Feb. 2026.
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