Kalmar "Arithicy" ta samo asali ne daga kalmomin Helenanci "Aithmos," Ma'anar lamba, da "Metia, Ma'anar Rabu ne. Kalmomi, ko jumla, sannan kuma fassara waɗannan ƙimar don samun fahimi cikin yanayin ko yin tsinkaya game da nan gaba. A takaice dai, aikin amfani da ƙa'idodi masu lissafi don hango ko hasashen nan gaba ko samun fahimi cikin yanayin. Kalmar tana da alaƙa da jerin maginin Harry, wanda aka koyar da ita a matsayin batun Makarantar Maita da Wizardry.