unutterable
un-ut-ter-a-ble
adjective
Too intense or extreme to be expressed or described in words.
"He felt unutterable despair."
Thesaurus
Synonyms: uncommunicative, incommunicative, unpronounceable, unspeakable, untellable, indefinable, ineffable, unexpressible, indescribable, inexpressible, unnameable, sacred