maldecir
/maldeˈθiɾ/ · A1 · verb
to damn, to curse
mal + decir = to speak ill, hence to curse (like malediction)
From Latin maledicere: male (badly) + dicere (to say). English malediction is the same root, and bendecir (to bless) is its opposite. It conjugates like decir in most tenses: maldigo, maldije.