/pay"bak'/ , n.
1. the period of time required to recoup a capital investment.
2. the return on an investment: a payback of 15 percent tax-free.
3. the act or fact of paying back; repayment.
4. something done in retaliation: a really vicious payback for years of being snubbed.
[ 1955-60; n. use of v. phrase pay back ]