probable cause: Meaning and Definition of

prob'able cause'

Pronunciation: [key]
— Law. Law.
  1. reasonable ground for a belief, as, in a criminal case, that the accused was guilty of the crime, or, in a civil case, that grounds for the action existed: used esp. as a defense to an action for malicious prosecution.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.