Okla. Admin. Code § 165:32-1-3
The following words and terms, when used in this Chapter, shall have the following meanings, unless the context clearly indicates otherwise:
"Commission" means the Oklahoma Corporation Commission.
"Continuous direction" means the movement of a locomotive engine or engines, coupled with or without cars, over any public rail highway crossing in any direction and maintaining that direction until the crossing is unoccupied.
"Crossing surface" means a combination of material such as treated timbers, reinforced concrete panels, and composite or rubber tiles that are combined with rail components such as the flange way and flange filler, to produce a surface that makes it possible for vehicles to cross over the railroad track in comfort and safety.
"Noxious plants" means poison ivy, poison oak, or poison sumac, at any height or maturity.
"Public crossing" means a location where the tracks cross a road which is under the jurisdiction of and maintained by a public authority and which is open to public travel.
"Private Crossing" means a location where a physical crossing is present but the road does not meet the conditions for a public crossing and for which a private crossing agreement may have been entered into between landowner and railroad.
"Rank weeds " means all vegetation which can conceal or harbor rodents, refuse or vermin.
"Sight rectangle" means a rectangle which would have a beginning point from the center of the main track and the center point of the grade crossing extending along the center of the street or roadway approach for a distance of fifty feet (50') or to the railroad right-of-way property line, whichever is less, then extend along the property line for a distance of two hundred fifty feet (250') in either direction from the original beginning point.
"Sight triangle" means a triangle which would have a beginning point from the center point of the main track and the center point of the grade crossing extending along the center of the street or roadway approach for a distance of fifty feet (50') or to the railroad right-of-way property line, whichever is less, then extend at an angle until arriving at a point on the center of the main track two hundred fifty feet (250') from the original beginning point.
"Thickets" means any dense growth, briar patch, or wild shrubbery having stems or trunks one inch (1") or less in diameter.
"Trash" means, but is not limited to, refuse, litter, leaves, paper, combustible materials, offal, rubbish, waste, debris, and useless or unused or uncared for matter of all kinds.
Okla. Admin. Code § 165:32-1-3