discriminator
noun
Definitions
A person who discriminates or differentiates.
A test or variable, etc. that serves to distinguish between different things.
Example: Colour is not an effective discriminator when it comes to the spiciness of food.
Any of several electronic devices that convert some property of a signal into an amplitude whose value is proportional to the difference between the value of the input signal and that of a standard.
A feature of the seller's offering that differs from a competitor's offering and is important to the buyer in question.