a. [ Pref. un- not + speakable. ] Not speakable; incapable of being uttered or adequately described; inexpressible; unutterable; ineffable; as, unspeakable grief or rage. -- Un*speak"a*bly, adv. [1913 Webster]
Ye rejoice with joy unspeakable and full of glory. 1 Pet. i. 8. [1913 Webster]