Miss. Code Ann. § 63-3-139

(a) “Business district” means the territory contiguous to and including a highway when fifty percent (50%) or more of the frontage thereon for a distance of 300 feet or more is occupied by buildings in use for business. (b) “Residence district” means the territory contiguous to and including a highway not comprising a business district when the property on such highway for a distance of 300 feet or more is in the main improved with residences or residences and buildings in use for business.