天才
てんさい · tensai · JLPT N1 · noun
genius
天 — 一 (one/sky) above 大 (big person)
Originally a pictograph of a person (大) with an emphasized head, representing what is above — the sky or heavens. The top stroke evolved into 一, symbolizing the vast expanse overhead. From 'sky' it extended to mean 'day,' 'heaven,' and 'nature.'
才 — single component 才 (one stroke 一 + 亅 + 丿)
才 originally pictured a sprout breaking through the ground, symbolizing budding talent or potential. Over time it came to mean 'talent, ability' and also 'just now,' since a sprout marks a fresh beginning. It is itself a basic component used in characters like 材 and 财.