To assign a number to something; to count or number in relation to.
From Latin 'ad-' (to) combined with English 'number.' This archaic verb was formed to mean 'to add to a count' or 'to include in a numbered list.'
This is such an old and rarely-used word that you'd be impressive to know it—it means to count something or add it to a list of numbers, but English speakers now just say 'number' or 'count.'
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