IPA: /əˈkrəʊmətaɪz/
KK: /əˈkrōməˌtīz/
To remove color from something, making it colorless or neutral in tone.
The artist decided to achromatize the painting to give it a more subdued look.
Past: achromatized
Past Participle: achromatized
Achromatize is formed from "a-" (meaning without) and "chromatos" (from Greek, meaning color) and the suffix "-ize" (meaning to make or to cause to be). The word means to make something without color or to remove color from it.
Think of 'without' ('a-') and 'color' ('chromatos') to remember that 'achromatize' means to make something colorless.