'paradox' definitions:

Definition of 'paradox'

From: WordNet
noun
(logic) a statement that contradicts itself; "`I always lie' is a paradox because if it is true it must be false"

Definition of 'paradox'

From: GCIDE
  • paradox \par"a*dox\ (p[a^]r"[.a]*d[o^]ks), n.; pl. paradoxes (p[a^]r"[.a]*d[o^]ks*[e^]z). [F. paradoxe, L. paradoxum, fr. Gr. para`doxon; para` beside, beyond, contrary to + dokei^n to think, suppose, imagine. See Para-, and Dogma.] A tenet or proposition contrary to received opinion; an assertion or sentiment seemingly contradictory, or opposed to common sense; that which in appearance or terms is absurd, but yet may be true in fact. [1913 Webster]
  • A gloss there is to color that paradox, and make it appear in show not to be altogether unreasonable. --Hooker. [1913 Webster]
  • This was sometime a paradox, but now the time gives it proof. --Shak. [1913 Webster]
  • Hydrostatic paradox. See under Hydrostatic. [1913 Webster]