period (periodic table)中文什么意思

元素周期

• period:    n. 1. 时代；期；时期；期间；阶 ...
• periodic table:    【化学】元素周期表。
• the periodic table:    周期表

百科释义

In the periodic table of the elements, elements are arranged in a series of rows (or periods) so that those with similar properties appear in a column. Elements of the same period have the same number of electron shells; with each group across a period, the elements have one more proton and electron and become less metallic.