The quality or state of being fearsome; the property of inspiring fear or dread in others.
From 'fearsome' plus the noun-forming suffix '-ness,' creating an abstract noun that describes the quality itself. 'Fearsome' entered English in the 15th century from Scots and Northern English dialects.
The 'fearsomeness' of a creature matters more in stories than its actual danger—Tolkien understood that a dragon's legend and mystique are often more powerful than its physical threat, which is why medieval monsters were as much about narrative as biology.
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