noun
wasted money; idle money; dead money
Refers to money that is sitting unused, not earning interest or being put to productive use. Often used in personal finance or investment contexts.
銀行に預けたままの死に金を投資に回そう。
Let's put that idle money sitting in the bank into investments.
タンス預金は死に金だ。
Cash stashed in a drawer is dead money.
Compound of 死に (continuative form of 死ぬ, 'to die') and 金 ('money'). Literally 'dead money', referring to money that is not 'alive' or productive.