nebula

noun

neb·​u·​la ˈne-byə-lə 

plural nebulae ˈne-byə-ˌlē  -ˌlī  also nebulas

1

: any of numerous clouds of gas or dust in interstellar space

2

: galaxy sense 1b

especially : a galaxy other than the Milky Way galaxy

—not used technically

nebular

ˈne-byə-lər 

adjective

Did you know?

Nebula comes to us from Latin, where it means "mist" or "cloud." In its earliest English uses in the 1600s, nebula was chiefly a medical term that could refer either to a cloudy formation in urine or to a cloudy speck or film on the eye that caused vision problems. It was first applied to great interstellar clouds of gas and dust in the early 1700s. The adjective nebulous comes from the same Latin root as nebula, and it is considerably older, being first used as a synonym of cloudy or foggy as early as the 1300s. Like nebula, however, this adjective was not used in an astronomical sense until the mid-1600s.

Examples of nebula in a Sentence

Recent Examples on the Web

These conditions—two massive stars existing within a nebula and their very different properties—are outside the norm. —Christian Thorsberg, Smithsonian Magazine, 18 Apr. 2024

Kant was right: such nebulae truly were island universes, and the Milky Way was merely one among many. —Phil Plait, Scientific American, 4 Aug. 2023

Word History

Etymology

New Latin, from Latin, mist, cloud; akin to Old High German nebul fog, Greek nephelē, nephos cloud

First Known Use

1718, in the meaning defined at sense 1

Phrases Containing nebula

• planetary nebula

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Kids Definition

nebula

noun

neb·​u·​la ˈneb-yə-lə 

plural nebulas or nebulae -ˌlē 

-ˌlī

1

: any of many huge clouds of gas or dust in deep space

2

: galaxy sense 2

nebular

-lər 

adjective

Medical Definition

nebula

noun

neb·​u·​la ˈneb-yə-lə 

plural nebulas or nebulae -ˌlē  -ˌlī 

: a slight cloudy opacity of the cornea