\In*duc"tion gen"er*a`tor\
A machine built as an induction motor and driven above
synchronous speed, thus acting as an alternating-current
generator; -- called also {asynchronous generator}. Below
synchronism the machine takes in electrical energy and acts
as an induction motor; at synchronism the power component of
current becomes zero and changes sign, so that above
synchronism the machine (driven for thus purpose by
mechanical power) gives out electrical energy as a generator.