Relating to or pertaining to numbering together; connected to joint calculation or enumeration.
From Latin 'con-' (together) and 'numerarius' (relating to number, from 'numerus' meaning number). This is an extremely rare word appearing only in historical or specialized texts.
Conumerary is so obscure that even most dictionaries skip it—it was probably used in medieval Latin by scholars discussing how to count things together, and then it just... faded away as English developed other words.
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