#1 theorize v. [speculate, theorise, conjecture, hypothesize, hypothesise, hypothecate, suppose] to believe especially on uncertain or tentative grounds; "Scientists supposed that large dinosaurs lived in swamps". wn
#2 theorize v. construct a theory about; "Galileo theorized the motion of the stars". wn
#3 theorize v. form or construct theories; "he thinks and theorizes all day". wn
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