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definitions

spheno-

  1. a combining form meaning “wedge,” used in the formation of compound words: sphenography.
Also especially before a vowel, sphen-.

Origin of spheno-

< New Latin < Greek sphḗn wedge + -o- -o-
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for spheno-

spheno-

before a vowel sphen-

combining form
  1. having the shape of a wedgesphenogram

Word Origin for spheno-

from Greek sphēn wedge
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 spheno-

word-forming element meaning "wedge," from comb. form of Greek sphen "wedge," probably cognate with Old Norse spann "splinter," Old English spon "chip of wood" (see spoon (n.)).

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

spheno-

pref.
  1. Wedge; wedge-shaped:sphenocephaly.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.