circuit

1. The complete path between two terminals over which one-way or two-way communications may be provided.
2. An electronic path between two or more points, capable of providing a number of channels.
3. A number of conductors connected together for the purpose of carrying an electrical current.
4. An electronic closed-loop path among two or more points used for signal transfer.
5. A number of electrical components, such as resistors, inductances, capacitors, transistors, and power sources connected together in one or more closed loops.
6. A fully operative communications path established in the normal circuit layout and currently used for message, WATS access, TWX, or private line services. [47 CFR Pt.36-A]