Predicate and predicator

Predicate : any word (or sequence of words) which (in a given single sense) can function as the predicator of a sentence.
Hungry, in, crook, asleep are all predicates.
Predicator : A word that does not belong to any of the referring expressions and which, of the remainder, makes the most specific contribution to the meaning of the sentence.
- asleep is the predicator in Mother is asleep.
- Love is the predicator in The tall boy loved the Japanese girl.
- Standing is the predicator in James was standing there.

The verb be in its various forms (is, was, are, were, am) cannot be a predicator.
The term predicate identifies elements in the language system, independently of particular example sentences. Predicator identifies the semantic role played by a particular word (or group of words) in a particular sentence. It is possible to show the predicator of a sentence, but impossible to list the predicators of English. A simple sentence only has one predicator, although it may contain more than one instance of a predicate.
A tall, handsome stranger entered the shop.
This sentence have only one predicator enter, but the sentence also contains the words tall, handsome, stranger, and shop.