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: a cloud of gas and dust in space believed to develop into a star
Recent Examples on the Web
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'protostar.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
1947, in the meaning defined above
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Resources for protostar
Time Traveler for protostar
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More from Merriam-Webster on protostar
Britannica.com: Encyclopedia article about protostar
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playful or foolish behavior
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