Any structure or part thereof, or any natural object (such as
a tree, rock, shrub and the ground itself), or any device, whether
freestanding or attached to a building, vehicle or structure or painted
or represented thereon, which shall be used to attract attention to
any object, project, place, activity, person, institution, organization
or business, or which shall display or include any letter, word, model,
flag, banner, pennant, insignia, device or representation which is
in the nature of or which is used as an announcement, direction or
advertisement for commercial purposes or otherwise. Signs shall include
billboards, neon or lighted tubes, strings of lights, inflatables,
paintings or similar devices outlining, attached or hung upon any
part of a building, vehicle, structure, or otherwise on a lot, but
does not include the flag, pennant or insignia of any nation or group
of nations, or of any governmental agency.