From The Collaborative International Dictionary of English v.0.48 :
Verisimilitude \Ver`i*si*mil"i*tude\, n. [L. verisimilitudo: cf. OF. verisimilitude. See Verisimilar.] The quality or state of being verisimilar; the appearance of truth; probability; likelihood. [1913 Webster] Verisimilitude and opinion are an easy purchase; but true knowledge is dear and difficult. --Glanvill. [1913 Webster] All that gives verisimilitude to a narrative. --Sir. W. Scott. [1913 Webster]From WordNet (r) 3.0 (2006) :
verisimilitude n 1: the appearance of truth; the quality of seeming to be true