noun🔗ShareA chemical element (symbol La) with an atomic number of 57: a soft, ductile, silvery-white metal that tarnishes slowly when exposed to air."The chemistry student learned that lanthanum is a silvery metal used in some camera lenses. "elementsubstancematerialchemistryscienceChat with AIVocabulary GamePractice Reading
noun🔗ShareAn atom of this element."The chemistry student pointed to lanthanum on the periodic table and said, "An atom of lanthanum has 57 protons." "elementchemistrysubstancematerialscienceChat with AIVocabulary GamePractice Reading
