私房钱
sī fáng qián · HSK 7
secret stash of money
💰🤫 私 sī private + 房 fáng room + 钱 qián money = private-room money, a secret stash
钱 — metal radical 钅 + 戋 (small/shallow)
Originally a name for a spade-shaped bronze tool used as early currency in ancient China. The metal radical 钅 gives the meaning (metal coin), while 戋 supplies the sound and hints at 'small, thin pieces.' Over time the meaning shifted from the spade-coin itself to money in general.