Word Study
penta-
CIDE DICTIONARY
penta-, pref. [Gr. penta-, a later combining form of pe`nte five. See Five.].
- A combining form denoting five; as, pentacapsular; pentagon. [1913 Webster]
- Denoting the degree of five, either as regards quality, property, or composition; as, pentasulphide,
containing five sulfur atoms ; pentoxide,containing five oxygen atoms , etc. Also used adjectively. [1913 Webster]
OXFORD DICTIONARY
penta-, comb. form 1 five.
2 Chem. (forming the names of compounds) containing five atoms or groups of a specified kind (pentachloride; pentoxide).
2 Chem. (forming the names of compounds) containing five atoms or groups of a specified kind (pentachloride; pentoxide).
Etymology
Gk f. pente five
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