protoplanet
Americannoun
noun
Etymology
Origin of protoplanet
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
About 4.5 billion years ago, a dramatic event transformed the young Earth when a large protoplanet known as Theia struck our planet.
From Science Daily ● Nov. 23, 2025
The chaos would have influenced the size, location, and composition of the rocky planets, and many researchers believe it could also explain why a Mars-size protoplanet crashed into Earth around this time, creating the Moon.
From Science Magazine ● Apr. 16, 2024
A giant collision between the young Earth and a smaller protoplanet has long been the prevailing theory for the Moon’s formation.
From Scientific American ● Nov. 2, 2023
The collision was so powerful, it broke apart that impacting protoplanet, nicknamed Theia, and sent huge amounts of material into orbit around Earth—material that eventually coalesced into the moon.
From National Geographic ● Nov. 1, 2023
The most popular theory says that about 4.5 billion years ago, a Mars-size protoplanet slammed into Earth.
From New York Times ● Nov. 1, 2023
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
