(a) "Central business" means and includes comparison and convenience shopping; personal, professional, business and financial services; public and semipublic uses and other activities of a comparable nature which contribute to the economics and design of a compact commercial area as determined by the Board.
(b) "Community shopping center" means and includes retail outlets and service enterprises which lend themselves to the design and economics of a unified shopping center ten to forty acres in size.
(c) "Highway and general business" means and includes commercial uses requiring locations on major thoroughfares. Highway uses include motels, gas stations and restaurants. General and service businesses include auto and farm implement sales and services, building trades and services, commercial recreation and other commercial uses which do not lend themselves to a unified commercial center layout.
(d) "Institution and office" areas mean and include institutions of a charitable, philanthropic or religious nature; insurance and other regional offices; medical centers and other comparable uses as determined by the Board. These uses require spacious sites and are not large generators of traffic.
(e) "Neighborhood retail business" means retail establishments which cater to and can be located in close proximity to residential districts without creating undue vehicular congestion, excessive noise or other objectionable influence. To prevent congestion, local retail uses include only those enterprises which normally employ less than ten persons. Permitted uses include drugstores, beauty salons, barber shops, plus hardware stores and groceries of less than 10,000 feet of floor area. Other small businesses of an equally restricted and local nature may be permitted based on the discretion of the Board.