税金
ぜいきん · zeikin · JLPT N3 · noun
tax
💰🧾 税金 = tax (税 zei) + money (金 kin): tax money
金 (kin) means gold or money, as in 現金 genkin, cash. 税 (zei) means tax, as in 消費税 shōhizei, consumption tax. Together, zeikin is the money you owe as tax.
税 — grain radical 禾 + 兑 (exchange/phonetic)
税 combines 禾 (grain) with 兑 (exchange), which also hints at the sound. In ancient China taxes were paid in grain, so the character originally meant a levy of harvest given to the state. Its meaning later broadened to taxes and duties of any kind.
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'.