The quality or state of being companionable; friendliness and suitability for pleasant company.
From companionable + -ness (abstract noun suffix). A redundant-sounding term since companionable + -ity would do the same job, but English allows multiple pathways to create abstract nouns, creating synonyms.
English sometimes creates competing synonyms unnecessarily—we have companionableness, companionability, companionage, and companionable all describing similar concepts—revealing how the language evolved through layers of word-creation by different generations of speakers.
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