Outing (also Role Outing) is a term used in Mafia to describe the situation where a player announces any player (especially himself) as being a particular role. While the information given to the Goodies is beneficial, it is usually avoided in the event of a non-friendly RID Kill. Some hosts forbid role outing and impose penalties (typically a loss of ability) on anyone who breaks the rule. It is considered bad etiquette to ever out the role of another player needlessly.
A common exception to this rule is if a player announces the role of a player on a different faction, typically the baddie faction.