adj. 1. Of, relating to, or based on theory. 2. Restricted to theory; not practical or applied: theoretical physics. 3. Studying or working to develop theory. [Late Latin theōrēticus, from Greek theōrētikos, from theōrētos, observable, from theōrein, to look at; see THEOREM.] the′o·reti·cal·ly adv. |
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