Selectivity

n. state of being picky, choosiness; state of being selective; quality of being able to tune in to one particular frequency while blocking out other unwanted frequencies (Electronics)

The word selectivity has several meanings:Selectivity, the ability to notice/distinguish small differences. Also the words selectiveness, refinement and discrimination are used. Discrimination is also a cultural term.Electronic selectivityIn a database index, a measure for how many records will be retrieved for a given value of an attribute.In natural sciences selectivity characterises either how selective reactions occur amongst several pathways which are typical in particular for organic reactions; or selectivity characterises how selective one particular compound is recognized, or bound, by something else, e.g. by a protein, in a supramolecular host-guest complex, or by parts of a sensor. High selectivity is often called specificity. Selectivity (pharmacology) in pharmacology it is the preference of a drug for one mechanism of action over others that cause side effects.
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Noun
1. the property of being selective
(hypernym) property

A measure of the ability of a receiver to discriminate between a wanted signal on one frequency and unwanted signals on other frequencies. (188 )

the difference in removal rate between two material during an etching or CMP process.