Meaning of autotransformer

au•to•trans•form•er

Pronunciation: (ô"tō-trans-fôr'mur), [key]
— n. Elect.
  1. a transformer having a single coil that serves as both a primary coil and a secondary coil.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.