AC 60-14 lists three. First, and probably most important, is a lack of common experiences between the sender and receiver. The second barrier is a confusion between the symbol and that which is being symbolized. And third, overusing abstract terms will create problems. A lack of a common experience base is the problem in the example above.
Words are also merely symbols used to represent facts, ideas, objects, and experiences.
If you, the CFI, use inaccurate or inappropriate words to convey your ideas, describe objects, or discuss experiences, confusion results. It is important to use the proper words in your explanations to avoid this pitfall. Finally, using abstract terms too much leaves your listeners with only a vague notion of the message you tried to convey. Clearly, the first conjured up a picture of a high-wing, fabric, yellow, fun airplane to fly. Each of the others, in descending order, became less clear as to what was really being talked about.