驯
xùn · HSK 7
to tame
🐴 马 (horse) + 川 (river): a wild horse made calm as a flowing stream = to tame
The 马 horse radical carries the meaning; taming a horse is the classic sense, and the broader idea is bringing something under control gradually. Sound xun is close to soon: a tamed horse comes when called soon.
驯 — horse 马 + river 川 (phonetic)
A semantic-phonetic compound: 马 (horse) gives the meaning and 川 (chuān) hints at the sound. Originally meant to tame or train a horse, then broadened to taming animals generally and, by extension, being docile or submissive.