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{%type%} Definitions

WordNet 3.0Copyright Princeton University


Short "hint"

The collection of matter, in the process of condensation, from which a very large round object that moves around the Sun or another star is formed

Usage examples (13)
  • It was a tiny blip, settling down feather-light toward the surface of the snowball protoplanet.
  • He cut in maximum magnification on the screens, and the surface of the little protoplanet of frozen gases leaped up toward him.
  • New close-up images of Pallas from the Hubble Space Telescope reveal that the second largest asteroid in the solar system appears to be a protoplanet, as well.
  • In the scientific community a widespread theory is that the moon was created when a protoplanet called Theia collided with Earth, and that that was also the catalyst... for more
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