An amount of money that is well beyond pocket change or what you'd normally spend on any one thing but isn't in the same league expense wise as a new car or house.

An example could be a new computer that you might need to save up for a while to afford.

Another example might be eating at a really expensive restaurant. It's not costing you the same amount as a new computer, but it's still far more expensive then a typical meal.
Look, I think we're going to have to choose somewhere less expensive to eat. I love the food there but it costs a small fortune.

Yes, I know I need a new video card but I can't afford the small fortune that a lot of the ones you're recommending cost.
by Optomist with experience January 16, 2009
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a significant amount of money, especially more than expected
Don't pay a small fortune for dietary supplements that fail to deliver.
by The Return of Light Joker September 4, 2009
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