Blackwash is a compound of black + wash, coined as the opposite of whitewash ('to gloss over faults'), meaning to expose discreditable facts. The historical trail runs through blæc in Old English and wæscan in Old English. Morphologically, blackwash is transparent: it is a compound of black + wash, coined as the opposite of whitewash ('to gloss over faults'), meaning to expose discreditable facts. Used as a verb and noun, blackwash now means "defame or expose discreditable facts about someone; the opposite of whitewash", so the present definition can be read against the older forms and meanings. The same lexical family is also visible in related forms such as black, wash, and whitewash. The modern word remains analyzable through its parts, which makes the semantic connection unusually direct.