1. very big reward or financial gain, the positive result of a set of actions
a huge financial/personal payoff
A 'payoff' is an advantage or benefit that can be obtained from doing something. This phrase refers particularly to (but not always) a monetary gain that occurs because of something. A 'huge payoff' is an advantage or benefit which is over the odds: "The money I invested early on had a huge payoff." "Investing in mentorship programs rarely has the huge payoff that employers expect."