A Point Source is origin of a pollutant Discharge from a discrete conveyance typically thought of as an effluent from the end of a pipe.
Other /More definition:
A Point source is a single identifiable source that discharges pollutants into the environment. Examples are smokestack, sewer, ditch, or pipe. See non-Point source.
Other /More definition:
Point source is the single identifiable source that discharges pollutants into the environment. Examples include the smokestack of a power plant or an industrial plant, drainpipe of a meatpacking plant, chimney of a house, or exhaust pipe of an automobile. Compare nonpoint source.