Tetra-
Pronunciation : Tet"ra-.
Etymology : [Gr. Four.]
Definition : 1. A combining form or prefix signifying four, as in tetrabasic, tetrapetalous.
2. (Chem.)
Defn: 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.
Source : Webster's Unabridged Dictionary, 1913