Also especially before a vowel, dec-.
Compare deci-, deka-.

Origin of deca-

< Greek deka-, combining form of déka ten; cognate with Latin decem Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for deca-


deka-, before a vowel dec- or dek-

  1. denoting ten: decagon . In conjunction with scientific units the symbol da is used

Word Origin for deca-

from Greek deka
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 deca-

before a vowel, dec-, word-forming element meaning "ten," from Latinized comb. form of Greek deka "ten" (see ten). In the metric system, "multiplied by ten;" while deci- means "divided by ten."

Online Etymology Dictionary, © 2010 Douglas Harper

deca- in Medicine


  1. Ten:decane.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

deca- in Science


  1. A prefix that means “ten,” as in decahedron, a polygon having ten faces.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.