An electric generator that produces alternating current.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "alternator" in a sentence
"When the driver presses the accelerator pedal again, the clutch between the engine and the starter-alternator is closed, causing the still turning flywheel to restart the engine without consuming any electrical current."
"Saturn is preparing the so-called “Green Line” line of hybrids for sale later this year, using a simplified electric motor/generator in place of a conventional alternator, which is supposed to cost several thousand dollars less than a hybrid from competitors."
"GM apparently decided that changing the alternator was the ticket, which they did; however, the whine got WORSE."