Definition of "Sale" :

noun: a particular instance of selling

"He has just made his first sale."

noun: the general activity of selling

"They tried to boost sales."

noun: an occasion (usually brief) for buying at specially reduced prices

"They held a sale to reduce their inventory."

noun: an agreement (or contract) in which property is transferred from the seller (vendor) to the buyer (vendee) for a fixed price in money (paid or agreed to be paid by the buyer)

"The salesman faxed the sales agreement to his home office."

noun: the state of being purchasable; offered or exhibited for selling

"You'll find vitamin C for sale at most pharmacies."