French frontière

← Spanish frontera (mention)

← French front (suffix)

← French ière (suffix)

← Italian frontiera (mention)

← Portuguese fronteira (mention)

→ English frontier (mention)

→ Catalan frontera (cognate)

→ Corsican fruntiera (cognate)

→ Spanish frontera (cognate)

→ French transfrontière (prefix)

→ Italian frontiera (cognate)

→ Norman frontchiéthe (cognate)

→ Portuguese fronteira (cognate)

→ Romanian frontieră (mention)