n. The state or quality of being achromatic; as, the achromatism of a lens; achromaticity.
n. The state of being free of colors, not emitting or separating into colors.
n. Achromatopia.
the GNU version of the Collaborative International Dictionary of English
n. The state or quality of being achromatic; ; achromaticity.
The Century Dictionary and Cyclopedia
n. The state or quality of being achromatic; absence of coloration: as, to secure perfect achromatism in a telescope.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. the visual property of being without chromatic color
Word Usage
"Very occasionally a person lacks all color-receptors and is completely color-blind, a condition called achromatism (ay-kroh'muh-tiz-um; "no color" G)."