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definitions

septi-

a combining form meaning “seven,” used in the formation of compound words: septilateral.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for septi-

septi-

1

before a vowel sept-

combining form

sevenseptivalent

Word Origin for septi-

from Latin septem

septi-

2

combining form

septumsepticidal
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 septi-

before vowels sept-, word-forming element meaning "seven," from Latin septem (see seven).

Online Etymology Dictionary, © 2010 Douglas Harper
septi- in Medicine

septi-

pref.

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