级
jí · HSK 2
grade
📊 级 = 糸 (silk) + 及 (reach) — silk threads ranked by grade
The 糸 radical points to silk/thread, while 及 supplies the sound (jí) and the sense of 'reaching a step.' Originally a rank or grade of silk thread; now any level, rank, or grade — school year, stair step, or class tier.
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.'