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{%type%} Definitions

WordNet 3.0Copyright Princeton University


Short "hint"

A hypothetical gaseous cloud of dust and atoms in space believed to develop into a star.

Usage examples (40)
  • Since then, stars have formed by the collapse of small, dense core regions in large, cold protostar, which is hot and bright because of energy generated by gravitational...
  • A protostar begins as an invisible concentration of gas deep inside a cloud.
  • So, each planet, sun, protostar and gas giant image is like an individual painting.
  • The brown dwarf is a protostar that never achieves enough mass to become an actual star. for more
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