beˈlievableness [f.prec. + -ness.] The quality of being believable; credibility. a1679T. Goodwin Wks. IV. i. 88 The credibility and believableness, as I call it, of those promises.Ibid. (1864) VIII. 116 Gives a subsistence to the object of faith that doth put into it..a being of believableness.