arm, ability, talent
腕 centers on the arm as a physical limb, and by extension the skill or ability one wields with it, like talent.
腕 combines the flesh radical ⺼ (body part) with 宛, which likely contributes the sound ワン. The character originally referred to the arm.
The left side ⺼ is flesh, and the right side 宛 looks like a bent arm with a hand at the end. Picture a muscular arm flexing: that's 腕.
For ワン, imagine a strong arm winning an arm-wrestling match: one -> ワン, and the winning arm shows real talent.
arm
wristwatch; watch
right arm
ability; skill; facility
ability; capability; skill
left arm
strong arm
remarkable ability; mastery; brilliant technique
upper arm
upper arm
strength in one's arms; physical strength; muscular strength
one arm
push-up (exercise); press-up
ability; capability; competence; skill
bracelet; bangle
push-up
showing off one's physical strength; relying on one's physical strength in a fight
highly skilled; skillful; very capable; competent; able
folding one's arms
armband; arm band; brassard