Opposite of 清 (clear). Literal use: 浑浊 (muddy) and 污浊 (foul, polluted). In linguistics it also names a voiced consonant, contrasted with a voiceless 清 one.
Left water radical, the side-form of 水. The base image is cloudy, sediment-filled water, which extends to anything impure or corrupt. Opposite of the equally water-radical 清.
Right 虫 serves as a simplified phonetic, its reading drifting toward zhuó. It contributes no insect meaning here; in traditional 濁 the right side was a fuller phonetic that the simplification replaced.
