barrel distortion
noun
,
Optics.
1.
a distortion produced by a lens in which the magnification decreases toward the edge of the field.
Compare
pincushion distortion
.
Origin
1885-90
British Dictionary definitions for
barrel distortion
barrel distortion
noun
1.
(
photog
) distortion of an image produced by an optical system that causes straight lines at image margins to bulge outwards