/ Dictionary / Index H Horsehead Nebula: Meaning and Definition of Find definitions for: Horse'head Neb"ula Pronunciation: [key] a dark nebula in the constellation Orion, composed of opaque cosmic dust and resembling the head of a horse. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. horsehead horsehide Related Content Daily Word Quiz: nonchalant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language