informal sentence Consider it done; OK; it is agreed. "How much for this used car?" Bill asked. "Two thousand," the man answered. "I'll give $1,500," Bill said. "It's a deal!" the owner answered as they sealed the transaction.
IT'S A DEAL
Meaning of IT'S A DEAL in English
American idioms English vocabulary. Английский словарь американских идиом. 2012