Where I am from I-95 is the major highway or "SLAB" that I drive on. This can be a SLAB of concrete, SLAB of tar or if u'za back country boy then ur SLAB is a dirtroad. In down South Florida I-95 is my SLAB.
I was ballin' on my way to Tampa and my Brother EROS called. He asked where I was at and I replied "I'm Northbound on the SLAB, bout to hit the turpike".