polar circle definition by Webster's New World
polar circle definition by American Heritage Dictionary
nounThe American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
- The Arctic Circle.
- The Antarctic Circle.
polar circle - Science Definition
The Arctic Circle or the Antarctic Circle.