@kennethamy,
All three of the theories of linguistic meaning you named are incorrect. I know you used the word, "term," but I think you mean word or concept.
Words are symbols for concepts, but when we talk about words we usually mean the concepts they represent. A simple explanation of this is that I and my spanish friend both have the same concept of what I call an onion. The language word I use for that concept is "onion." The word my Spanish friend uses is, "cebolla." "Onion," and, "cebolla," are different words for the same concept.
The purpose of all concepts is to identify things that exist, physical entities, attributes, relationships, and actions as well as those things that only exist as concepts or the abstract.
What a word means is whatever it identifies. The word apple, for example, means an actual apple. If you ask a young boy what he would like, he might point at an apple in a bowl and say, "I would like one of those," or, he might say, "I would like an apple." The word apple performs the same function as pointing at an apple and saying, "one of those." It identifies what the child wants.
The word apple means any apple that exists, past, present, or future, real or imagined. It means an apple with all its possible attributes, relationships, and all that can possibly learned about it, whether or not any of those attributes, relationships, or facts are known or not. That is why the word apple means exactly the same thing when used by a botanist or by a little boy. The botanist knows an enormous amount about an apple and the little boy knows very little, but it is about an apple that both their knowledge is about. The concept apple only identifies what that knowledge is about, not the knowledge itself.
Please see the artice
Knowledge