1 a : progress, advance <in the process of time> b : something going on : proceeding
2 a (1) : a natural phenomenon marked by gradual changes that lead toward a particular result <the process of growth> (2) : a continuing natural or biological activity or function <such life processes as breathing> b : a series of actions or operations conducing to an end; especially : a continuous operation or treatment especially in manufacture

1 : the act of selling; specifically : the transfer of ownership of and title to property from one person to another for a price
2 a : opportunity of selling or being sold : demand b : distribution by selling
3 : public disposal to the highest bidder : auction
4 : a selling of goods at bargain prices
5 plural a : operations and activities involved in promoting and selling goods or services <vice-president in charge of sales> b : gross receipts

— for sale : available for purchase

— on sale 1 : for sale
2 : available for purchase at a reduced price