rigid designator

noun

1. logic an expression that identifies the same individual in every possible world: for example, "Shakespeare" is a rigid designator since it is possible that Shakespeare might not have been a playwright but not that he might not have been Shakespeare

Example Sentences

Water is a rigid designator, while “the substance that fills the lakes and oceans” is descriptive.

From New York Times

The term “rigid designator,” which has entered the Oxford English Dictionary, defines the type of linguistic expression that refers to the same thing in all possible worlds, as opposed to a descriptive designator, which may not.

From New York Times