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1. A message expressing an opinion based on incomplete evidence
   - guess, conjecture, surmise, surmisal, speculation, hypothesis
    
2. A hypothesis that is taken for granted
   "any society is built upon certain suppositions"
   - assumption, supposal
    
3. The cognitive process of supposing
   - supposal

Derived forms: suppositions

See also: suppose, suppositional

Type of: conjecture, hypothesis, opinion, possibility, theory, view

Encyclopedia: Supposition