"Business district" means the territory contiguous to and including a street when, within any six hundred feet along such street, there are buildings in use for business or industrial purposes, including but not limited to hotels, banks or office buildings, railroad stations and public buildings which occupy at least three hundred feet of frontage on one side or three hundred feet collectively on both sides of the street.
(Ord. 321 Art. 1 § 2(d)(1), 1974).