"Storage compartment" refers to a designated space or area where you can keep and store items. It is like a small room or box where you can put things away for safekeeping or to keep them organized. Full definition
Accessories that support an active lifestyle, such as a torch and a camera, are positioned in storage compartments in the boot. (topspeed.com)
Some car seats also come with storage compartments for your children to keep toys in. (mommystroller.com)
The large storage compartment under the seat is a great way to carry baby - parent accessories and also move around easy with your shopping while still in the mall. (ultimatestrollerguide.com)