Meaning of informatory double

inform'atory dou"ble

Pronunciation: [key]
— Bridge. Bridge.
  1. a double intended to inform one's partner that one has a strong hand and to urge a bid regardless of the strength of his or her hand. Also calledCf. business double.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.