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?

The history of nebula belongs not to the mists of time but to the mists of Latin: in that language nebula 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. Nebula 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, this adjective was not used in an astronomical sense until centuries later.

Examples of nebula in a Sentence

Recent Examples on the Web

Groups can see the amazing arms of spiral galaxies, colorful nebulas or details on planets directly on the computer screen. —John Natale, Hartford Courant, 26 Dec. 2024

Stars are born in clouds of gas and dust, which is why nebulas are hotbeds for new star formation. —Samantha Mathewson, Space.com, 26 Dec. 2024

The darkness in the nebula is mostly due to thick dust blocking the light of the stars behind it. —Ars Technica, 1 Mar. 2024

Day 8 of the 2024 Space Telescope Advent Calendar: a mysterious nebula. —Alan Taylor, The Atlantic, 8 Dec. 2024

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