aspherical

or a·spher·ic

[ey-sfer-i-kuh l or ey-sfer-ik]

adjective Optics.

(of a reflecting surface or lens) deviating slightly from a perfectly spherical shape and relatively free from aberrations.

Origin of aspherical

First recorded in 1920–25; a-⁶ + spherical

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018