In semantics, a predicate is concept (property or n-ary relation) that is attributed to a given (set of) argument(s) in a predication. Constituents with the function of a predicate are called predicate terms. However, the distinction between 'predicates' and 'predicate terms' is often not made, especially in syntactic research.
In predicate logic, a predicate is often represented in (small) capitals followed by its argument(s) in parentheses. For example, the predicate denoted by the word man can be represented as man, and if the property of being a man is attributed to Fred, this is represented as man(Fred). Alternatively, inverted commas are often used to mark (semantic) predicates as such and to distinguish them from natural language , e.g. man'(Fred). When a predicate takes two arguments (denotes a relation rather than a property), the arguments are usually separated by commas (e.g. like(Fred,Mary) for Fred likes Mary). Put differently, the predicate like takes a pair of entities (rather than a single entity) which functions as an argument of that predicate.
In traditional grammaticography, a predicate combines with a subject to form a sentence, and the ascribes a property to the subject referent (e.g. Socrates is the subject in the sentence Socrates is mortal and is mortal is the predicate).
- Gamut, L.T.F. 1991. Logic, language, and meaning, Univ. of Chicago Press, Chicago.