(formerly) any celestial object that appears nebulous, hazy, or fuzzy, and extended in a telescope view.
a faint opacity in the cornea.
cloudiness in the urine.
any liquid medication prepared for use as a spray.
- neb·u·lar, adjective
- non·neb·u·lar, adjective
- pre·neb·u·lar, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use nebula in a sentence
Caldwell 56, a blue-hued planetary nebulaPlanetary nebulae were named as such because early astronomers thought they looked like planets from afar.
It’s a dark nebula, meaning interstellar dust blocks out the glow of gas and stars behind it.
To celebrate the scope’s third decade, NASA released 30 new images of dazzling nebulae, star clusters, and galaxies—all taken by Hubble.
Caldwell 58, a reflection nebulaDiscovered in 1861, NGC 6729 or Caldwell 58 is what’s known as a reflection nebula—a cloud of star-forming gas that lights up thanks to a young, hot, nearby star.
Taken in connection with what we know of the nebulæ, the proof of Laplace's nebular hypothesis may fairly be regarded as complete.Outlines of the Earth's History | Nathaniel Southgate Shaler
Of course it would be understood that tidal evolution is in no sense a rival doctrine to that of the nebular theory.Time and Tide | Robert S. (Robert Stawell) Ball
Allied to the preceding hypothesis is Shapley's nebular hypothesis.Climatic Changes | Ellsworth Huntington
In the nebular railway the passengers would almost require such a warning.Young Folks' Library, Volume XI (of 20) | Various
This “cosmological nebular theory” was based entirely on the mechanical phenomena of gravitation.
British Dictionary definitions for nebula
astronomy a diffuse cloud of particles and gases (mainly hydrogen) that is visible either as a hazy patch of light (either an emission or a reflection nebula) or an irregular dark region against a brighter background (dark nebula): Compare planetary nebula
opacity of the cornea
cloudiness of the urine
any substance for use in an atomizer spray
- nebular, adjective
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
Scientific definitions for nebula
A visible, thinly spread cloud of interstellar gas and dust. Some nebulae are the remnants of a supernova explosion, others are gravity-induced condensations of the gases in the interstellar medium which in certain cases may become a site for the formation of new stars. The term was formerly used of any hazy, seemingly cloudlike object, including what are now recognized as other galaxies beyond the Milky Way; it is restricted now to actual clouds of gas and dust within our own galaxy.♦ Nebulae are generally classified as bright or dark. Among the bright nebulae are cold clouds that reflect light from nearby stars (reflection nebulae) and hot, ionized clouds that glow with their own light (emission nebulae). Dark nebulae-cold clouds that absorb the passing light from background stars-are called absorption nebulae. See more at star.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Cultural definitions for nebula
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.