mad money

noun, Informal.
1.
a small sum of money carried or kept in reserve for minor expenses, emergencies, or impulse purchases.
2.
a small sum of money carried by a woman on a date to enable her to reach home alone in case she and her escort quarrel and separate.
Origin
1915-20
Slang definitions & phrases for mad money

mad money

noun phrase
  1. Money carried by a woman with which to pay her way home if her escort becomes offensive
  2. Money saved by a woman against the time when she wants to make an impulsive or therapeutic purchase (1922+)