Final answer:
A scientific theory is 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 experimentation.
Step-by-step explanation:
A scientific theory is 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 experimentation.
**Theories** are explanations of natural phenomena and are not just guesses or speculations.
In contrast to a hypothesis, which is a tentative explanation for an observation, a scientific theory is thoroughly tested and confirmed explanation for a set of observations or phenomena.