sharp

(gold) + (horny) + (older brother)
★★★☆☆
15 strokes

Onyomi

EI

Fonzie says "EYYYY!!" as he sticks his sharp thumb up, to indicate his satisfaction.

Mnemonic

Older brother has a sharp mind so he winds up earning a lot of gold.

Kunyomi

するど*い sharp 1/2 KANA
★★★☆☆

Jukugo

鋭敏(えいびん)

quick-witted, keen. ★☆☆☆☆
(sharp) + (agile / sensitive) = 鋭敏 (quick-witted, keen.)