Final answer:
A theory is a well-substantiated explanation of some aspect of the natural world that is supported by a body of evidence and remains unfalsified despite rigorous testing.
Step-by-step explanation:
A theory in the scientific community is defined as a comprehensive explanation of some aspect of nature that is supported by a vast body of evidence. It is much more than just a simple hypothesis, which is initially a tentative explanation for scientific observations. A hypothesis becomes a theory after being subjected to rigorous testing through experimentation and observation, and when it consistently predicts and explains the phenomena it pertains to.
Contrary to what one may think, a hypothesis or a theory can never be conclusively proven true because of the possibility that future evidence may contradict it. However, the more evidence that supports a hypothesis, the more confidence scientists have in considering it to be true. The iterative process of experimentation, hypothesis testing, and refining leads to theories that serve as reliable models of understanding our world, as they encapsulate a great deal of scientific knowledge and factual consistency.
For example, the theory of gravity explains why objects fall towards the ground, and despite extensive testing, it remains unrefuted and widely accepted. This principle also applies to theories in biology, such as the theory of evolution, which offers a robust explanatory framework for the diversity of life on Earth.