Meaning of variocoupler

var•i•o•cou•pler

Pronunciation: (vâr"ē-ō-kup'lur), [key]
— n. Elect.
  1. a transformer having coils with a self-impedance that is essentially constant but a mutual impedance that can be varied by moving one coil with respect to the other.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.