効力
こうりょく · kouryoku · JLPT N2 · noun
consequence
🎯 効 = effect, 力 = power: the power to produce an effect
効 (kou) means effect or result, and 力 (ryoku) means power or strength. Together they name the power a thing has to produce its intended result, like a medicine's efficacy.
力 — pictograph of a plow or arm muscle
力 originated as a pictograph of an ancient plow, the main tool requiring physical exertion in early agriculture. Some scholars also see it as a flexed arm showing muscle. From this concrete image it broadened to mean 'strength, power, force, effort'.