pocket money
A small amount of money one carries to spend on nonessential things. I give the kids 10 bucks at the start of the week as a bit of pocket money. If they spend it all, then that's all they get till the next Monday. The company has given me a bit of pocket money while I'm here, so why don't we go find somewhere nice to eat?
pocket money
Also, spending money. Cash for incidental or minor expenses, as in They don't believe in giving the children pocket money without asking them to do chores, or Can I borrow a dollar? I'm out of all my spending money. The first term, dating from the early 1600s, alludes to keeping small sums in one's pocket; the second alludes to money that may be spent (as opposed to saved) and dates from the late 1500s.