Tetra- (?). [Gr. tetra-, from tesares, tettares, four. See Four.] 1. A combining form or prefix signifying four, as in tetrabasic, tetrapetalous.
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2. (Chem.) 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.
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