Md. Code, Transportation § 8-725

(a) In this part the following words have the meanings indicated.

(b) (1) In this definition, “commercial or industrial activity” means any activity generally recognized as commercial or industrial by local zoning authorities in this State, except for the following activities:

(i) Outdoor advertising;

(ii) Agricultural, forestry, ranching, grazing, farming, and related activities, including wayside fresh produce stands;

(iii) Activities normally or regularly in operation less than 3 months of the year;

(iv) Transient or temporary activities;

(v) Activities conducted in a building principally used as a residence; and

(vi) Railroad tracks and minor sidings.

(2) “Commercial or industrial area” means any area along the side of a highway:

(i) That is reserved under a local zoning ordinance or regulation for business, commerce, or trade;

(ii) That is not zoned and on which there are located one or more permanent structures devoted to a commercial or industrial activity or on which a commercial or industrial activity is conducted, whether or not a permanent structure is located there, including the area that, along or parallel to the edge or pavement of that side of the highway, extends 660 feet from the outer edges of the regularly used buildings, parking lots, or storage or processing areas of the commercial or industrial activity.

(c) “Double–faced” means abutting and facing the same direction.

(d) “Federal–aid primary highway” means any State highway that is part of the national federal–aid primary system as of June 1, 1991, or any highway on the national highway system, as designated by the Administration and approved by the United States Secretary of Transportation under Title 23 of the United States Code.

(e) “Scenic byway” means a transportation corridor designated by the Administration as having special scenic, historic, recreational, cultural, archaeological, or natural qualities that have been recognized as such through legislation or some other official declaration.