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Theory Definition & Meaning - Merriam-Webster
Theory - Wikipedia
THEORY | English meaning - Cambridge Dictionary
THEORY Definition & Meaning | Dictionary.com
Theory Definition & Meaning | Britannica Dictionary
theory noun - Definition, pictures, pronunciation and usage notes ...
The Structure of Scientific Theories - Stanford Encyclopedia of …
theory noun - Definition, pictures, pronunciation and usage notes ...
What is Theory? | Oxford Research Encyclopedia of International …
Full article: Theories and Models: What They Are, What They Are …