unspeakableness

uncountable

The condition or quality of being unspeakable.

Japanese Meaning

言葉で表現できない状態、すなわち、表現不可能な品質 / 口に出して表現することができない状態または性質

The unspeakableness of the ancient ritual left even the most seasoned archaeologists at a loss for words.

その古代の儀式の言い表せない性質により、最も経験豊かな考古学者でさえ言葉を失った。

Sense（1）

The condition or quality of being unspeakable.

Obviously, it's the unspeakableness, the sheer horror of it, that is motivating some news organizations.