Dacia Syllabification: (Da·ci·a)Pronunciation: /ˈdāSH(ē)ə/Definition of Dacia an ancient country in southeastern Europe in what is now northwestern Romania. It was annexed by Trajan in ad 106 as a province of the Roman Empire. Derivatives DacianPronunciation: /ˈdāSH(ē)ən/ adjective & noun Dacia in other Oxford dictionaries Definition of Dacia in the British & World English dictionary