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[ap-luh-nat-ik] /ˌæp ləˈnæt ɪk/
adjective, Optics.
free from spherical aberration and coma.
Origin of aplanatic
1785-95; a-6 + Greek planá(ein) to wander + -tic. See planet
Related forms
aplanatically, adverb Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for aplanatic
  • The case of aplanatic refracting surfaces is considered.
British Dictionary definitions for aplanatic


(of a lens or mirror) free from spherical aberration
Derived Forms
aplanatically, adverb
Word Origin
C18: from Greek aplanētos prevented from wandering, from a-1 + planētos, from planaein to wander
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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aplanatic in Medicine

aplanatic ap·la·nat·ic (āp'lə-nāt'ĭk)
Of or relating to an optical lens that is free from chromatic or spherical aberration.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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