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