ouble ole - ouble hrow. This term refers to the construction of a switch. The "poles" refer to the number of independent sets of contacts exist in the switch. For example, a double pole switch can independently switch two separate circuits. The "throws" reflect the number of positions the switch element can occupy. A simple on-off switch is a single-pole switch; a double throw switch can connect a single wire to either of two other wires. DPDT switches are commonly used to control accessory circuits - in one throw, the instrument signal is routed through the EQ; in the other throw, the EQ circuit is bypassed.

double pole double throw (on a switch or relay)

A switch that simultaneously routes each of two independent inputs to one or two outputs.