Definition of overcolour in English:

overcolour

Pronunciation /ˌəʊvəˈkʌlə/

verb

(US overcolor)
  • To colour excessively; (chiefly in extended use) to represent too strongly or in an exaggerated way.

Origin

Early 19th century; earliest use found in Samuel Taylor Coleridge (1772–1834), poet, critic, and philosopher. From over- + colour.