doubter

from WordNet (r) 3.0 (2006)

doubter
    n 1: someone who habitually doubts accepted beliefs [syn:
         {skeptic}, {sceptic}, {doubter}]
    2: someone who is doubtful or noncommittal about something [syn:
       {agnostic}, {doubter}]

from The Collaborative International Dictionary of English v.0.48

Doubter \Doubt"er\, n.
   One who doubts; one whose opinion is unsettled; one who
   scruples.
   [1913 Webster]

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