The quality or state of being compassionate; deep sympathy and concern for others' suffering.
From 'compassionate' plus the noun-forming suffix '-ness' (from Germanic roots meaning 'state' or 'condition'). The suffix has been used since Old English to create abstract nouns from adjectives.
Adding '-ness' to adjectives is such an old English pattern that it's invisible to us, yet it's created thousands of abstract qualities—compassionateness being one of the most humanistic.
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