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definitions

ionopause

[ahy-on-uh-pawz]
noun
  1. the transitional zone between the ionosphere and the mesosphere.

Origin of ionopause

iono- + pause
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ionopause

ionopause

noun
  1. the transitional zone in the atmosphere between the ionosphere and the exosphere, about 644 km (400 miles) from the earth's surface
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012