achromatopsia a·chro·ma·top·si·a (ə-krō'mə-tŏp'sē-ə) or a·chro·ma·top·sy (ə-krō'mə-tŏp'sē)
n.
A severe congenital deficiency in color perception, often associated with nystagmus and reduced visual acuity. Also called achromatic vision, monochromatism.
| an obscure term ostensibly referring to a lung disease caused by silica dust, sometimes cited as one of the longest words in the English language. |
| given to using long words. |