Atramentous refers to something that is very dark, typically black or deep brown in color. Therefore, antonyms for "more atramentous" would be terms used to describe brighter, lighter, or more colorful objects. These antonyms may include words like white, pale, light, bright, vivid, colorful, vibrant, and multicolored, among others. While atramentous may describe something that is mysterious or imposing, its antonyms would describe things that are happy or cheerful, such as a rainbow or bright yellow sunshine. Antonyms for atramentous can also be used figuratively to describe contrasting emotions or feelings, such as hope instead of despair.