pin-money

/P IH1 N M AH1 N IY0/
noun
  1. 1

    An allowance of money given by a man to his wife or to other dependents for their personal, discretionary use.

  2. 2

    A relatively small sum of cash kept in one's personal possession for routine expenses or incidental purchases; an amount of money which is not particularly significant.

Source: https://en.wiktionary.org/wiki/pin%20money, https://en.wiktionary.org/wiki/pin-money