Also especially before a vowel, tetr-.

Origin of tetra-

< Greek, combining form of téttara, neuter of téttares four
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British Dictionary definitions for tetra-


before a vowel tetr-

combining form
  1. fourtetrameter

Word Origin for tetra-

from Greek
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for tetra-

word-forming element meaning "four," from Greek tetra-, combining form of tettares, tessares "four" (see four).

Online Etymology Dictionary, © 2010 Douglas Harper

tetra- in Medicine


  1. Four:tetradactyl.
  2. Composed of or containing four atoms, molecules, or groups:tetrasaccharide.
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