arreglar
/areˈɡlaɾ/ · A2 · verb
to fix, to repair, to mend
🔧 a- + regla (rule) + -ar: to bring something back to rule, into order
From regla, the Spanish for rule or ruler, itself from Latin regula. To arreglar is to put a thing back in line with the rule: a broken machine, a messy room, or a quarrel. English regulate and regular share the same root.