Arithmetic or the practice of calculating with numbers; an archaic or obsolete term for mathematical computation.
From Old English or Middle English, possibly related to Arabic 'al-khwarizmi' (a famous mathematician) or Arabic 'qisma' (division). The term was used in medieval times for arithmetic and numerical operations.
Augrim is a beautiful fossil word—it shows how medieval English borrowed and adapted the term for arithmetic, possibly from the same Arabic root that gave us 'algorithm'!
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