[1] : WordNet (r) 2.0

hypothesize
     v : to believe especially on uncertain or tentative grounds;
         "scientists supposed that large dinosaurs lived in
         swamps" syn: speculate, theorize, theorise, conjecture,
          hypothesise, hypothecate, suppose
see also:
speculate theorize theorise conjecture hypothesise hypothecate 
suppose 

[2] : Moby Thesaurus II by Grady Ward, 1.0

20 moby thesaurus words for "hypothesize":
   analyze, apply reason, deduce, entertain a theory,
   espouse a theory, generalize, have a theory, infer,
   intellectualize, logicalize, logicize, philosophize,
   provide a rationale, rationalize, reason, speculate, syllogize,
   synthesize, theorize, use reason

Hypothesize >> H Words
Hypothesize, definition of term: Hypothesize
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