素
sù · HSK 7
plain
🧵 Bottom half is 糸 (silk); 素 is raw undyed silk, so it means plain and white.
The 糸 silk radical sits at the base, and the strokes above show fibers before dyeing. Undyed silk is white and unadorned, which extends to the senses plain, simple, and basic. Pronounced sù.
素 — silk 糸 + sheng 𠂹 (hanging threads)
Originally depicted raw, undyed silk hanging to dry, with the silk radical 糸 below and strands above. From this came the meaning 'plain, unadorned, white,' then extended to 'basic element' or 'plain/simple' in general. The 'vegetarian' sense developed later from the idea of plain, unembellished food.