#acromatism

• Achromatism — The property of an optical system to transmit or reflect light without producing chromatic aberrations, allowing the formation of a sharp image without fringing. In a medical or biological context, the term refers to the total absence of colored pigments in a tissue or anatomical structure, or a visual anomaly where the subject perceives the world exclusively in shades of white, black, and gray.
• Achromatism — A secondary or historical graphic and spelling variant of the term 'acromatism'; it defines the structural property of an optical system to transmit white light beams without splitting them into parasitic chromatic components. In older technical texts or 19th-century manuscripts, it represented the transcription standard before modern terminological standardization.