electrum Syllabification: (e·lec·trum)Pronunciation: /iˈlektrəm/Definition of electrum noun a natural or artificial alloy of gold with at least 20 percent silver, used for jewelry, especially in ancient times. Origin: late Middle English: via Latin from Greek ēlektron 'amber, electrum'electrum in other Oxford dictionaries Definition of electrum in the British & World English dictionary