back seat
n 1. a seat at the back, esp of a vehicle
2. informal a subordinate or inconspicuous position (esp in the phrase take a back seat)
adj 3. relating to or taking place on the back seat of a vehicle
4. of a subordinate nature
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014