名詞
一組金屬元素，包括銅同金；當氫原子同佢嘅原子之一形成化合物嘅時候，呢種金屬所顯示嘅氫原子價數超過一個 (chemistry) transition metal; any of a group of metal chemical elements including copper and gold that show more than one valency, the number of hydrogen atoms that can combine with one of its atoms to form a compound