了解
りょうかい · ryoukai · JLPT N1 · noun
comprehension
了 — pictograph of swaddled child with no arms
了 originally depicted an infant wrapped in swaddling cloth, with the arms hidden or bound — a variant of 子 (child) without the arms. From 'finished wrapping' it extended to mean 'completed' or 'finished,' which is its main modern grammatical use as an aspect particle marking completed action.
解 — horn 角 + knife 刀 + ox 牛
解 is an ideograph showing hands using a knife (刀) to separate the horn (角) from an ox (牛). The original meaning was to butcher or dismember an ox, which broadened to 'untie, separate, loosen,' and then extended figuratively to 'explain' or 'understand'—to take something apart mentally.