[1] : The Collaborative International Dictionary of English v.0.48

unutterable \unut"terable\, a.
   not utterable; incapable of being spoken or voiced;
   inexpressible; ineffable; unspeakable; as, unutterable
   anguish.
   1913 webster

         sighed and looked unutterable things.    --thomson.
   1913 webster -- unut"terableness, n. --
   unut"terably, adv.
   1913 webster
see also:
unut"terableness unut"terably 

[2] : WordNet (r) 2.0

unutterable
     adj 1: too sacred to be uttered; "the ineffable name of the deity"
            syn: ineffable, unnameable, unspeakable
     2: defying expression or description; "indefinable yearnings";
        "indescribable beauty"; "ineffable ecstasy";
        "inexpressible anguish"; "unspeakable happiness";
        "unutterable contempt"; "a thing of untellable splendor"
        syn: indefinable, indescribable, ineffable, unspeakable,
         untellable
     3: very difficult to pronounce correctly; "an unpronounceable
        foreign word"; "unutterable consonant clusters" syn: unpronounceable
see also:
ineffable unnameable unspeakable indefinable indescribable untellable 
unpronounceable 

[3] : Moby Thesaurus II by Grady Ward, 1.0

72 moby thesaurus words for "unutterable":
   arcane, awesome, awful, cabalistic, censored, classified, close,
   closed, concealed, cryptic, dark, divine, enigmatic, esoteric,
   heavenly, hermetic, hidden, holy, hush-hush, incommunicable,
   inconceivable, incredible, indefinable, indescribable, ineffable,
   inenarrable, inexpressible, innominable, inviolable, inviolate,
   latent, marvelous, mysterious, noncommunicable, numinous, occult,
   prodigious, religious, restricted, sacred, sacrosanct, secret,
   smothered, spiritual, stifled, suppressed, top secret, ulterior,
   unbelievable, unbreatheable, undefinable, under security,
   under wraps, undisclosable, undisclosed, undivulgable, undivulged,
   unimaginable, unmentionable, unnameable, unrevealable, unrevealed,
   unspeakable, unspoken, untellable, untold, untouchable, unuttered,
   unwhisperable, venerable, wonderful, wondrous

Unutterable >> U Words
Unutterable, definition of term: Unutterable
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