electric nigger means: A person who has been taken advantage of in labor terms, is treated as if he or she were a slave, or gopher. He/she will be expected to behave and act like a plugged-in appliance, or machine that does the job without any gratitude or respect. The mechanical laborer. (in Open Dictionary, added by Severino Ortiz)

What else does electric nigger mean?

An individual who feels like a mechanical slave and is only used for their needs. They do what they are told and won’t question. (in Open Dictionary, added by Rebekah Trujillo)

A worker who is treated badly and disrespected. A term that is associated with an appliance. One simply plugs it in, and it works. gopher. (in Open Dictionary, added by Damián López)