Latin sērius

→ English swear (cognate)

→ English serious (derived)

→ Spanish serio (derived)

→ French sérieux (derived)

→ Italian serio (derived)

→ Latin seriosus (mention)

→ Norman séthieux (derived)

→ Portuguese sério (learned borrowing)

→ Serbo-Croatian seriozan (derived)

→ Serbo-Croatian сериозан (derived)

→ Serbo-Croatian seriozno (derived)

→ Serbo-Croatian сериозно (derived)