Most greyish is considerably challenging to find antonyms for. However, some antonyms for the word greyish that could describe a shade that's brighter, more vibrant, or colorful are vivid, bright, vibrant, intense, brilliant, and brilliant. Greyish refers to a dull, muted, or desaturated grey color that is often lackluster, uninspiring, or monotonous. In contrast, synonyms for greyish would be unpleasant, lifeless, or bleak. Nevertheless, with the right context, greyish could be an appropriate term to use, especially when describing certain environments, objects, or moods. It all depends on the writer's perspective on the matter.