definition of
unutterable

[1] #1 unutterable s. [ineffable, unnameable, unspeakable] too sacred to be uttered; "the ineffable name of the Deity". wn

[2] #2 unutterable s. [indefinable, indescribable, ineffable, unspeakable, untellable] defying expression or description; "indefinable yearnings"; "indescribable beauty"; "ineffable ecstasy"; "inexpressible anguish"; "unspeakable happiness"; "unutterable contempt"; "a thing of untellable splendor". wn

[3] #3 unutterable s. [unpronounceable] very difficult to pronounce correctly; "an unpronounceable foreign word"; "unutterable consonant clusters". wn