Electrical Code…
The circuit conductors between the final over-current device protecting the circuit and the outlet(s).
A branch circuit that supplies energy to one or more outlets to which appliances are to be connected and that has no permanently connected luminaires that are not part of an appliance.
A branch circuit that supplies two or more receptacles or outlets for lighting and appliances.
A branch circuit that supplies only one utilization equipment.
A branch circuit that consists of two or more ungrounded conductors that have a voltage between them, and a grounded conductor that has equal voltage between it and each ungrounded conductor of the circuit and that is connected to the neutral or grounded conductor of the system.
(National Electrical Code® 100-1)