Transformer/trænsˈfɔːrmər/ Definition 1 of 3Pro Tip 1/3Technical Usage Used in electrical and engineering contexts to describe equipment. The technician installed a transformer in the power plant. Pro Tip 2/3Specific Function Refers to a component that specifically changes electrical current voltage. We need a transformer to step up the voltage for this circuit. Pro Tip 3/3Safety Device Transformers also provide safety by isolating circuits. Ensure the safety transformer is connected before starting.