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a predicate (mathematics) is either a relation or the boolean-valued function that amounts to the characteristic function or the indicator function of such a relation.

a predicate (logic) is a fundamental concept in first-order logic.

a predicate (grammar) is one of the two constituent parts of a sentence. It is the rest of the sentence apart from the subject. For instance, in the sentence "All good things come to an end" the "come to an end" is the predicate, whereas the subject is "all good things."

a predicate (computer programming) is an operator or function which returns a boolean value, true or false, and predication is a choice to execute or not to execute a given instruction based on the content of a machine register.

a predicate (geographic information) is similar to a computer programming predicate, in that it is an operator or function which returns a boolean value, but in this case based on spatial relationships such as within, contains, intersects, touches or overlaps.

a predicate (RDF) is a trait or aspect about that resource that is being described.

In Bertrand Russell's theory of types, a predication (type theory) is an act of typing, that is, assigning a type. A definite description in fact contains a claim of existence.