unutterable

Suddenly the world had become a vast waste, and he was in it alone, helpless and unutterably weary.

A faint perfume, having a sort of sweetness, but which yet was unutterably revolting, made itself perceptible to the nostrils.

What did Christabel see in her, at times, so unutterably horrible?

There was something so unutterably sad about Felicita's condition that it awed the simple, cheerful nature of Madame.