Yellow-marked refers to something that is marked with yellow spots, stripes or patterns. The antonyms of the word yellow-marked include plain, unmarked, untouched, unblemished, unadorned, and uncolored. These words signify the lack of any particular mark, design, or pattern on the surface of an object or material. A plain surface is smooth and without any decoration, and an unblemished surface is free from any spots, scratches or damage. An uncolored surface, on the other hand, lacks any tint, shade or hue. Therefore, these antonyms convey the opposite meaning of yellow-marked, indicating the absence of any type of mark or pattern on the surface.