Capable of being or having a companion; suitable for companionship.
From compani- + -able, an obsolete or variant form of 'companionable.' This shows how English once had multiple competing forms for the same concept, with different authors choosing different spellings.
Medieval and early modern texts are full of spelling variants like 'companiable' and 'companionable'—before dictionaries standardized English, writers had tremendous freedom, and you can sometimes figure out what region or century a manuscript came from just by how they spelled these friendship words.
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