a preliminary performance or test of something, as of the operation of a ship or the effectiveness of a play.
Origin of trial run
First recorded in 1900–05
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
a test drive in a vehicle to assess its performance
a test or rehearsal of something new or untried to assess its effectiveness
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012