How is the use of the word theory in science differently from it's more common use?

In science, the term "theory" refers to a well-substantiated explanation of natural phenomena, based on a body of evidence and repeated testing, such as the theory of evolution or the theory of relativity. In contrast, the common use of "theory" often implies a mere guess or hypothesis lacking substantial evidence. This distinction highlights that scientific theories are robust frameworks that can predict outcomes and withstand rigorous scrutiny, whereas colloquial usage may suggest uncertainty or speculation.