静まる
しずまる · shizumaru · JLPT N2 · verb-godan
to quieten down
静 (しず, quiet) + まる (become): becomes quiet, so it means calm down
The verb is built from the noun stem 静 (しず, quiet) plus the intransitive ending まる, which marks a change of state. Together they mean to become quiet. Compare 静かにする, to make things quiet.
静 — 青 (blue/green) + 争 (contend/strive)
A semantic-phonetic compound. The right side 争 ('contend') originally suggested calming a dispute, while 青 lent the sound and a sense of clarity. Together they convey stillness after strife has settled, giving the modern meaning 'quiet, calm, still.'