- a combining form occurring in loanwords from Greek, meaning “five” (Pentateuch); on this model, used in the formation of compound words (pentavalent).
Also especially before a vowel, pent-.
Origin of penta-
< Greek pent-, penta-, comb. forms representing pénte five
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- fivepentagon; pentameter; pentaprism
from Greek pente five
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 penta-
word-forming element meaning "five, containing five," from Greek penta- (before a vowel pent-), comb. form of pente "five," related to Aeolian pempte (see five), with -a- by analogy of hepta-, ennea-, deka-.
Online Etymology Dictionary, © 2010 Douglas Harper
- Containing five atoms, molecules, or groups:pentose.
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