竖
shù · HSK 7
to erect
📏 竖 = vertical stroke; the | line you draw top-to-bottom when writing hanzi
竖 — 臤 (firm) on top + 立 (stand) below
竖 is a semantic-phonetic compound. The bottom 立 (stand) gives the meaning of standing upright or vertical, while the top 臤 supplies the sound. Originally it referred to standing something up, and by extension came to mean 'vertical' or a young servant who stands in attendance.