Areas generally characterized by low-density residential development (e g , 1 to 5 dwelling units per acre) and limited commercial uses
The Suburban and Central Business District (CBD) designations refer to a particular geographic area within a metropolitan statistical area (MBA) Suburban is defined as including all office inventory not located in the CBD (see definition of Central Business District)
pertains to the culture, manners, and customs of a residential area outlying a city
The meaning of 'sub' is, falling nearly in the category of, that is, not quite urban; missing some of the important components to be defined as urban See urban