the·o·rize [ th ə rz, thr z ](past and past participlethe·o·rized, present participlethe·o·riz·ing, 3rd person present singularthe·o·riz·es)
verb
Definition:
1. intransitive verb speculate: to speculate or form a theory about something
2. transitive verb conceive of theoretically: to conceive of something in a theoretical way Research scientists were able to theorize the existence of the particle before it was actually discovered.