Word Study
Tetra-
CIDE DICTIONARY
Tetra-, [Gr. te`tra-, from te`sares, te`ttares, four. See Four.].
- A combining form or prefix signifying four, as in tetrabasic, tetrapetalous. [1913 Webster]
- A combining form (also used adjectively) denoting four proportional or combining parts of the substance or ingredient denoted by the term to which it is prefixed, as in tetra-chloride, tetroxide. [1913 Webster]
OXFORD DICTIONARY
Tetra-, comb. form (also tetr- before a vowel)
1 four (tetrapod).
2 Chem. (forming names of compounds) containing four atoms or groups of a specified kind (tetroxide).
1 four (tetrapod).
2 Chem. (forming names of compounds) containing four atoms or groups of a specified kind (tetroxide).
Etymology
Gk f. tettares four
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