高级
gāojí · HSK 2
high-level
⭐ 高级 = 高 (high) + 级 (level/grade) → high-level
高 means high or tall; 级 means level, grade, or rank (as in 年级 school grade). Together they literally mean high-grade, used for premium, advanced, or high-class things.
高 — pictograph of a tall building/tower
高 is a pictograph of a tall structure, likely a watchtower or multi-story gate, with a roof on top, an upper chamber, and a base below. From this concrete image of height it extended to the general meanings 'tall,' 'high,' and figuratively 'lofty' or 'noble.'
级 — silk radical 纟 + 及 jí (phonetic)
级 is a semantic-phonetic compound. The silk radical 纟 originally referred to threads or the steps/ranks of silk cords used to mark official grades. The right side 及 (jí) supplies the sound. Over time the meaning shifted from 'cord-marked rank' to general 'level, grade, class.'