Which of the following refers to representations that are shown or depicted by diagrams?

The term that best fits the definition of representations shown or depicted by diagrams is "diagrammatic." Diagrams are visual representations that illustrate or explain particular concepts, processes, or structures, making the term "diagrammatic" the most appropriate choice. This word specifically relates to the use of diagrams, emphasizing the graphic nature of the representations being discussed.

In contrast, "concomitant" refers to something that accompanies or is related to another thing but does not specifically involve diagrams. "Consummate" generally means to complete or fulfill something to the highest degree, which is unrelated to the representation of information through diagrams. "Commingle" means to mix or blend together, which does not pertain to the idea of depicting information through diagrams.

Thus, the choice of "diagrammatic" directly correlates with the context of the question and accurately describes the nature of representations depicted by diagrams.