As used in this chapter, the following terms shall have the meanings indicated:
A gathering in a public area or park at which more that 25 persons are, or can reasonably be expected to be, in attendance.
An organized procession, except funeral processions, upon any public street, sidewalk or alley.
Any march or procession consisting of people, animals or vehicles, or combination thereof, except funeral processions, upon any public street, sidewalk or alley which does not comply with normal and usual traffic regulations or controls.
An assembly of persons upon any public street, sidewalk or alley which impedes or tends to impede pedestrian or vehicular traffic.