trial purchase

During the first two weeks of the operation the price of the test brand was lowered to encourage a trial purchase.

Most railroads ordered a few units from several builders in their first, trial purchase, but the second, volume order usually went to EMD.

The Fourt-Woodlock equation (sometimes misspelled Fort-Woodlock equation) is a market research tool to describe the total volume of consumer product purchases per year based on households which initially make trial purchases of the product and those households which make a repeat purchase within the first year.