American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "planetoid" in a sentence
"We don't have a good definition for planet, but this thing is a little bit smaller than something I'd be willing to call a planet, so we sort of made up the name planetoid to try to describe what it is."
"BROWN: Actually, as it stands right now, I would say there only eight planets, because I would say Pluto really deserves to be called a planetoid, too."
"It's not very big, but suddenly the planetoid is the talk of the solar system."