A special and exclusive legal advantage, allowance, permission or right such as a benefit, exemption, power or immunity.
From Canadian Union of Postal Workers v. Canada Post Corporation at 1994 3 FC 140:
"Some advantage to an individual or group of individuals, a right enjoyed by a few as opposed to a right enjoyed by all."
An example would be the special privileges that some persons have in a bankruptcy to recoup their debts from the bankrupt’s estate before other, non-privileged creditors.
Another would be the privilege given to persons while on the floor of a legislature and that for defamatory statements made in that venue, the defamor has an absolute privilege; a complete shield against any defamation claim.
New Brunswick Broadcasting Corp. v Nova Scotia, 1993 1 SCR 319:
"Privilege in this context denotes the legal exemption from some duty, burden, attendance or liability to which others are subject."
This extraordinary protection is justified as stated by Justice l'Heureux-Dube in A v B, at 1995 4 SCR 536:
"The doctrine of privilege acts as an exception to the truth-finding process of our adversarial trial procedure. Although all relevant information is presumptively admissible at trial, some probative and trustworthy evidence will be excluded to serve other overriding social interests. The same principles apply to exempt, completely or partially, particular communications arising out of certain defined relationships from disclosure in judicial proceedings. Since the existence of privilege impedes the realization of the central objective of our legal system in order to advance other goals, the question of privilege is essentially one of public policy."
Or MacArthur v Meuser at 1997 146 DLR 4th 125 (Ontario):
"Privilege applies in situations where it would be better, as a matter of policy, that individuals should occasionally suffer harm if the alternative is to impair freedom of communication between persons standing in a certain relationship. There are two classes of privilege: absolute and qualified."
See also Canadian Defamation Law.