現金
げんきん · genkin · JLPT N3 · noun
cash
💵 現金 = present + money: money that is right here, in hand
現 (gen) means present or actual, as in 現在 (now), and 金 (kin) means money or gold. Cash is money that is actually present, not a card or a promise. A sound hook: genkin sounds like 'gen-uine coin'.
金 — roof 亼 + two dots (metal nuggets) + earth 土
Originally a pictograph of metal nuggets buried in the earth beneath a covering, with the two dots representing pieces of ore. It first meant 'metal' broadly, then narrowed to 'gold' as the most precious metal, and by extension 'money'.