Final answer:
The correct answer is 'False'; a scientific theory is a well-substantiated explanation supported by a significant body of facts and evidence, extensively verified by observations and experiments, and is not merely an unverified suggestion.
Step-by-step explanation:
The statement "A scientific theory is defined as a suggested but unverified explanation for observed phenomenon" is false. A scientific theory is much more than a suggestion; it is a well-substantiated explanation of some aspect of the natural world. This explanation is based on a body of facts that have been repeatedly confirmed through observation and experimentation. Scientific theories are supported by lots of evidence and are tested and verified across many different experiments by various researchers.
In science, the term theory differs from the colloquial usage where it might be equated with a guess. Scientific theories, such as the theory of gravity, the theory of evolution, and germ theory, are reliable accounts that describe and explain important features of the natural world. They are comprehensive and supported by a significant body of evidence that has accumulated over time, and they enable scientists to make accurate predictions about as yet unobserved phenomena.