1. Prefix. Forming compound words having the sense of ‘four’. ¹
¹ Source: wiktionary.com
Medical Definition of Tetra-
1.
1. A combining form or prefix signifying four, as in tetrabasic, tetrapetalous.
2. 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.
Origin: Gr, from, four.
(29 Oct 1998)