乙
yǐ · HSK 5
second
乙 = ancient pictograph of a bent sprout; now means 'second' (after 甲)
In the 天干 (Heavenly Stems) sequence — 甲乙丙丁 — 乙 is the second stem, so it stands for 'B' or 'second' in ordered lists. Shape derives from a curved seedling form in oracle bone script.
乙 — single stroke pictograph
乙 is an ancient pictograph traditionally said to depict a sprout bending as it pushes through soil, or alternatively a curved fish or bird form. It became the second of the ten Heavenly Stems, used for ordering and enumeration. Today it mostly survives in that ordinal sense and as a stroke-name.