penta- Meaning, Definition & Usage

Pen"ta-
Etymology
Gr. , a later combining form of five. See Five.
Definitions
  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.

Webster 1913