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definitions

halo-

  1. a combining form meaning “salt,” used in the formation of compound words (halophyte); sometimes specialized as a combining form of halogen (halothane).
Also especially before a vowel, hal-.

Origin of halo-

< Greek, combining form of háls salt
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for halo-

halo-

hali- or before a vowel hal-

combining form
  1. indicating salt or the seahalophyte
  2. relating to or containing a halogenhalothane

Word Origin for halo-

from Greek hals, hal- sea, salt
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 halo-

before vowels hal-, word-forming element meaning "salt, sea," from Greek hals (genitive halos) "a lump of salt, salt generally," in Homer, "the sea," from PIE *sal- "salt" (see salt (n.)).

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

halo-

pref.
  1. Salt:halophilic.
  2. Halogen:halide.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.