unutterable

adj.

说不出的；难以形容的；说不出口；

1. He has already gone through unutterable agonies.
   他已受了种种难言的痛苦。
2. He was silent, and I guessed at his unutterable depression.
   他不讲话了,但我猜他有满腔说不出的郁闷。

Emily Dickinson's Unutterable Word
Unutterable horror : a history of supernatural fiction
Unutterable shame/unuttered guilt : semantics, aporia, & the possibility of Mabo
‘The unutterable and the dream’. Aspects of Wilde's reception in Central Europe 1900–1922
Graphic Testimonies: Voicing the Unutterable in Auto/Biographics of War
Uttering the unutterable modern western poets' endeavors to solve the problem of language impotence
The Utterable and Unutterable Anthropological Meaning of the Body in the Context of Organ Transplantation
Things Unutterable. Paul's Ascent to Paradise in Its Greco-Roman, Judaic, and Early Christian Contexts by James D. Tabor
"The Neglected, the Unutterable Verlaine": Arthur Symons, the Saturday review and French literature in the 1890s
"What is Impossible to Speak about..."Phenomenon of "Unutterable Demands"and Social Risks in Modern Society