Results

Definition of theory : 1. A doctrine, or scheme of things, which terminates in speculation or contemplation, without a view to practice; hypothesis; speculation.
2. An exposition of the general or abstract principles of any science; as, the theory of music.
3. The philosophical explanation of phenomena, either physical or moral; as, Lavoisier's theory of combustion; Adam Smith's theory of moral sentiments.
4. The science, as distinguished from the art; as, the theory and practice of medicine.

Synonyms:

plea, rationale, opening, systemization, outlook, reason, data, code, scheme, dogma, principles, doctrine, law, method, premise, postulate, foundation, approach, possibility, thesis, conditions, possible action, presupposition, possibleness, surmise, surmisal, postulation, philosophy, belief, basis, argument, provision, system, assumption

ideation, observation, perception, conception, inspiration, vision, principle, consideration, concept, opinion, thought, design, image, brainstorm, idea, reflection, plan, supposition, notion, inkling

presumption, hypothesis, prophecy, speculation, guess, imagination, fantasy, conjecture

Usage examples:

• Not much of the theory, but a good deal of the practice. - "Hills of the Shatemuc", Susan Warner.
• I shouldn't wonder, said she, if that's a Rhaetian theory- a Rhaetian man's theory. - "The Princess Virginia", C. N. Williamson A. M. Williamson.
• But she had her own theory. - "The Flaw in the Crystal", May Sinclair.