The word 单纯 is formed by combining the character 单, meaning "single", "alone", or "one-fold", with the character 纯, meaning "pure", "unmixed", or "genuine". Together, they create a conceptual compound where the idea of "singularity" or "singleness" (单) merges with the idea of "purity" (纯) to evoke the abstract quality of something being simple, unadulterated, and without complexity or ulterior motive, like a single, undiluted substance or a mind focused on one pure, uncomplicated thought.