The quality or state of having no emotion; complete detachment from feeling.
From emotionless + -ness (suffix that forms abstract nouns from adjectives). This double-suffixing (emotion-less-ness) is a productive pattern in English for creating abstract qualities.
Emotionlessness can range from peaceful detachment to clinical coldness—it's the noun form that lets us discuss the absence of feeling as a psychological or philosophical condition, like in discussions of depression or autism.
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