Penta- 表示“五”之义
Penta- \Pen"ta-\ [Gr. ?, a later combining form of ? five. See
{Five}.]
1. A combining form denoting five; as, pentacapsular;
pentagon.
2. (Chem.) Denoting the degree of five, either as regards
quality, property, or composition; as, pentasulphide;
pentoxide, etc. Also used adjectively.