cálculo
/ˈkalkulo/ · B1 · noun · m
calculation
🧮🪨 From Latin calculus, a small pebble: Romans counted with stones
Cálculo comes from Latin calculus, meaning pebble, because Romans did arithmetic by moving stones on a counting board. That's why English has calculate. In Spanish, cálculo can also mean a kidney stone, so the word kept both senses.