a combining form meaning “equal,” used in the formation of compound words: equimolecular.
Origin of equi-
Middle English < Latin aequi-, combining form representing aequus equal
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for equi-
equal or equallyequidistant; equilateral
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 equi-
word-forming element meaning "equal," from Latin aequi-, comb. form of aequus "equal, even" (see equal (adj.)).
Online Etymology Dictionary, © 2010 Douglas Harper
Science definitions for equi-
A prefix that means equal or equally, as in equidistant.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.