the inner, or shorter, track of a racecourse.
an advantageous position in a competitive situation.
Origin of inside track
An Americanism dating back to 1855–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
the inner and therefore shorter side of a racecourse
informal a position of advantagethe local man has the inside track in this contest
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