In circuit theory, a super-node is a theoretical construct that can be used to solve a circuit. This is done by viewing a voltage

Voltage

Voltage, otherwise known as electrical potential difference or electric tension is the difference in electric potential between two points — or the difference in electric potential energy per unit charge between two points...

 source on a wire as a point source voltage in relation to other point voltages located at various nodes in the circuit, relative to a ground

Ground (electricity)

In electrical engineering, ground or earth may be the reference point in an electrical circuit from which other voltages are measured, or a common return path for electric current, or a direct physical connection to the Earth....

node assigned a zero or negative charge.

Each super-node contains two nodes, one a non-reference node and another node that may be a second non-reference node or the reference node. Super-nodes containing the reference node have one node voltage variable. For Nodal circuit analysis, the super-node construct is only required between two non-reference nodes.