单薄
dān bó · HSK 7
frail
🍂 single + thin: so thin it stands alone, flimsy and frail
单 means single or alone, 薄 means thin. Together they describe something so thin and solitary it lacks substance — weak, frail, flimsy like a single autumn leaf barely holding on.
单 — 叩 (two mouths 口) over 甲 (shield/armor)
Originally a pictograph of a forked hunting weapon or shield with two prongs at the top. The ancient form shows a Y-shaped tool, later stylized into the modern shape. The meaning shifted from the weapon to 'single' or 'one,' possibly because it was a single-handed tool.
薄 — grass radical 艹 + 溥 (pǔ, phonetic)
薄 is a semantic-phonetic compound. The grass radical 艹 on top hints at the original meaning — thin, sparse vegetation or undergrowth. The lower part 溥 supplies the sound. From 'sparse plants' the meaning broadened to 'thin', 'slight', or 'meager' in general use.