a dry run

dry run

A practice session or test designed to identify and correct possible problems. Let's do a couple dry runs of your speech so you feel totally comfortable with it for tomorrow's ceremony. The theater group did a dry run of the play to iron out any technical problems before opening night.
See also: dry, run

a dry run

or

a test run

A dry run or a test run is something that you do to practise before you do it at a more important time. We'll have a dry run at getting you in and out of the clothes quickly. More than 10,000 people were expected and council chiefs said it would be a dry run for the Olympic celebrations.
See also: dry, run