request for money; touch (for money)
Refers to the act of asking someone for money, often implying a somewhat brazen or persistent request. The English slang 'touch' captures a similar informal, sometimes presumptuous feel.
He hit up his friend for money.
I received a letter asking for money.
Compound of 金 (money) and 無心 (here meaning 'to ask for something', derived from the older sense 'free from ulterior motives', ironically used for brazen requests).