noun, plural he·li·os. Informal.

a heliogram.
a heliograph.

Nearby words

  1. helicotrema,
  2. heliculture,
  3. helideck,
  4. heliencephalitis,
  5. heligoland,
  6. helio-,
  7. heliocentric,
  8. heliocentric parallax,
  9. heliochrome,
  10. heliodor

Origin of helio

by shortening


a combining form meaning “sun,” used in the formation of compound words: heliolatry.
Also especially before a vowel, heli-.

Origin of helio-

< Greek, combining form of hḗlios sun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for helio

British Dictionary definitions for helio


before a vowel heli-

combining form

indicating the sunheliocentric; heliolithic

Word Origin for helio-

from Greek, from hēlios sun

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 helio


word-forming element meaning "sun," from Greek helio-, comb. form of helios "sun" (see sol).

Online Etymology Dictionary, © 2010 Douglas Harper