Definitions of theory:
- noun: a belief that can guide behavior
Example: "The architect has a theory that more is less"
- noun: a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena
Example: "True in fact and theory"
- noun: a tentative theory about the natural world; a concept that is not yet verified but that if true would explain certain facts or phenomena
Example: "A scientific hypothesis that survives experimental testing becomes a scientific theory"
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