The condition or quality of being unspeakable.(noun)
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Use "unspeakableness" in a sentence
"I agree on all counts -- especially about The Big Snit, which is unspeakably awesome in its awesome unspeakableness."
"The unspeakableness of this drives the AP frantic with alliteration."
"Now and then the man in the intervals of his singing patted the dog, and spoke to him caressingly; and the dog looked at him with a gratitude which reached immensity through its unspeakableness."