* Germ is a general term for a microscopic organism, especially one that causes disease. This term was already in use before the theory was developed.
* Theory refers to a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment.
Therefore, the Germ Theory of Disease emerged as a scientific explanation for the origin of diseases, attributing them to the presence and action of these microscopic organisms, or "germs".
It was not a person or a specific event that named the theory, but rather the nature of the cause of disease that was identified by the theory itself.
