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definitions

sclero-

a combining form meaning “hard,” used with this meaning, and as a combining form of sclera, in the formation of compound words: sclerometer.
Also especially before a vowel, scler-.

Origin of sclero-

combining form of Greek sklērós hard
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for sclero-

sclero-

before a vowel scler-

combining form

indicating hardnesssclerosis
of or relating to the sclerasclerotomy

Word Origin for sclero-

from Greek sklēros hard
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 sclero-

before vowels scler-, word-forming element meaning "hard," from Latinized form of Greek sklero-, comb. form of skleros "hard," related to skellein "to dry up, parch," from PIE *skle-ro-, from root *skele- "to parch, wither."

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

sclero-

pref.

Hard:scleredema.
Hardness:sclerogenous.
Sclera:scleritis.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.