キョウ, ゴウ, つよ.い, つよ.まる, つよ.める, し.いる, こわ.い, すね
JLPT4 G2 S11 F112
The relevant bronzeware inscription form is a shape indicator suggesting the horned head of a beetle + 虫 insect → beetle. A seal inscription form adds 弓# bow, functioning as an abbreviated form of 彊 (strong, tautly stretched bow), leading to the meanings *strong*, *strength*, and *force* → *compel*; *coerce*; *intensify*. Returning to the seal inscription form, this referred to a hardshelled beetle, making 強 弓 + a variant form of the bronzeware inscription character (beetle).
[Full Kanji Etymology List]