aplanatic

adjective

ap·​la·​nat·​ic ˌa-plə-ˈna-tik 

: free from or corrected for spherical aberration

an aplanatic lens

Word History

Etymology

a- + Greek planasthai to wander — more at planet

First Known Use

1794, in the meaning defined above

Medical Definition

aplanatic

adjective

ap·​la·​nat·​ic ˌap-lə-ˈnat-ik, ˌā-plə- 

: free from or corrected for spherical aberration

an aplanatic lens

aplanatically

-i-k(ə-)lē 

adverb