calcium

Từ điển Oxford Advanced Learner 8th

cal·cium BrE [ˈkælsiəm] NAmE [ˈkælsiəm] noun uncountable (symb. Ca)
a chemical element. Calcium is a soft silver-white metal that is found in bones, teeth and ↑chalk.

Word Origin:
[calcium] early 19th cent.: from Latin calx, calc- ‘lime’, probably from Greek khalix ‘pebble, limestone’ + -ium.

• Từ đồng nghĩa / Synonyms:
  Ca, atomic number 20