The quality or state of being cowardly, shameful, or despicably fearful in one's actions and behavior.
From 'dastardly' plus the noun-forming suffix '-ness,' creating an abstract noun for the quality of cowardice and shameful behavior.
The word 'dastardliness' feels almost Dickensian when you say it—the multiple syllables make it sound like something worthy of dramatic Victorian disapproval!
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