depigmentation

This term is primarily used in clinical and dermatological contexts to describe the complete loss of melanin. It carries a sterile, medical tone and is distinct from hypopigmentation, which refers to a partial reduction in color rather than a total absence.

As an uncountable noun referring to a biological process or state, it does not typically take a plural form. When referring to specific areas of color loss, clinicians use partitive constructions such as patches of depigmentation or areas of depigmentation to quantify the condition.