Dyschromia

Part of speech: noun

Definitions

1. A condition characterized by unusual or irregular coloring of the skin
2. The presence of skin areas showing different pigmentation from normal
3. An occurrence where patches of skin display abnormal or uneven color

Etymology: Dyschromia is a medical term built entirely from Ancient Greek parts. The prefix "dys-" means "bad" or "difficult," and "chrôma" means "colour," so the combined sense is roughly "bad colouring." The suffix "-ia" is the common Greek-derived ending for conditions and states, as in "anemia" or "hypothermia." Because the word is a technical coinage rather than something that passed down through everyday speech, its exact date of entry into English is not something I can pin down from the source. What the construction shows is that it was assembled deliberately from classical building blocks, the same method used for most clinical vocabulary. Its meaning has stayed close to its parts: it names an abnormal pattern of skin colour, whether patches of lightness or darkness, and has changed little from its original sense.