stron ‧ ti ‧ um /ˈstrɒntiəm $ ˈstrɑːn-/ BrE AmE noun [uncountable]
[ Date: 1800-1900 ; Origin: Strontian , village in Scotland where a substance formed from strontium was discovered ]
a soft silver-white metal that is used to make ↑ firework s . It is a chemical ↑ element : symbol Sr