a combining form meaning “equal,” used in the formation of compound words: isochromatic; in chemistry, used in the names of substances which are isomeric with the substance denoted by the base word: isocyanic acid.
Also, especially before a vowel, is-.

< Greek, combining form of ísos equal Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To Iso-
World English Dictionary
iso- or (before a vowel) is-
combining form
1.  equal or identical: isomagnetic
2.  indicating that a chemical compound is an isomer of a specified compound: isobutane; isocyanic acid
[from Greek isos equal]
is- or (before a vowel) is-
combining form
[from Greek isos equal]

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
American Heritage
Medical Dictionary

iso- or is-

  1. Equal; uniform: isobar.

  2. Isomeric: isopropyl.

  3. Characterized by sameness with respect to species: isoantigen.

  4. Characterized by sameness with respect to genotype: isograft.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
American Heritage
Science Dictionary
  1. A prefix that means "equal," as in isometric, "having equal measurements."

  2. A prefix used to indicate an isomer of an organic compound, especially a branched isomer of a compound that normally consists of a straight chain. The isomer is characterized by a Y-shaped branch at the end of the chain that consists of two "prongs". Each prong consists of one carbon atom. Thus isopentane contains five carbon atoms like normal pentane, but arranged as a chain of three carbons plus a Y-shaped branch of two carbons at the end.

The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
Copyright © 2014, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature