Impugnable

from WordNet (r) 3.0 (2006)
impugnable
    adj 1: subject to being discredited
    
from The Collaborative International Dictionary of English v.0.48
Impugnable \Im*pugn"a*ble\, a.
   Capable of being impugned; that may be gainsaid.
   [1913 Webster]
    

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