Definition of "polar circle" []

• The Arctic Circle. (noun)
• The Antarctic Circle. (noun)

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.

• "Between the polar circle and the tropic, the cetaceous animals of the ocean grow to the length of 50, 80, or 100 feet, (Hist. des Voyages, tom.xv. p. 289."