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definitions

sidero-

1
  1. a combining form meaning “iron,” used in the formation of compound words: siderolite.
Also especially before a vowel, sider-.

Origin of sidero-

1
< Greek sidēro-, combining form of sídēros iron

sidero-

2
  1. a combining form meaning “star,” “constellation,” used in the formation of compound words: siderostat.

Origin of sidero-

2
< Latin sīder- (stem of sīdus) star-group + -o-
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for sidero-

sidero-

before a vowel sider-

combining form
  1. indicating ironsiderolite

Word Origin for sidero-

from Greek sidēros
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
sidero- in Medicine

sidero-

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