pa·ral·o·gism (pə-rāl'ə-jĭz'əm) n. A fallacious or illogical argument or conclusion.
[Late Latin paralogismus, from Greek paralogismos, from paralogos, unreasonable : para-, beyond; see para-1 + logos, reason; see leg- in Indo-European roots.] pa·ral'o·gist n., pa·ral'o·gis'tic adj.