mag ‧ ne ‧ si ‧ um /mæɡˈniːziəm/ BrE AmE noun [uncountable]
[ Date: 1800-1900 ; Language: Modern Latin ; Origin: magnesia ]
a common silver-white metal that burns with a bright white flame. It is a chemical ↑ element : symbol Mg
mag ‧ ne ‧ si ‧ um /mæɡˈniːziəm/ BrE AmE noun [uncountable]
[ Date: 1800-1900 ; Language: Modern Latin ; Origin: magnesia ]
a common silver-white metal that burns with a bright white flame. It is a chemical ↑ element : symbol Mg
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012