nebulous

adjective

neb·​u·​lous ˈne-byə-ləs How to pronounce nebulous (audio)
1
: of, relating to, or resembling a nebula : nebular
2
: indistinct, vague
… this nebulous thing called jazz.Josef Woodard
… the nebulous region between mere suspicion and probable causeW. R. LaFave & J. H. Israel
The plan is too nebulous.
nebulously adverb
nebulousness noun

Did you know?

Nebulous may sound other-worldly—after all, it’s related to nebula, which refers to a distant galaxy or an interstellar cloud of gas or dust—but its mysteriousness is rooted in more earthly unknowns. Both words ultimately come from Latin nebula, meaning “mist, cloud,” and as far back as the 14th century nebulous could mean simply “cloudy” or “foggy.” Nebulous has since the late 17th century been the adjective correlating to nebula (as in “nebulous gas”), but the word is more familiar in its figurative use, where it describes things that are indistinct or vague, as when Jack London wrote of “ideas that were nebulous at best and that in reality were remembered sensations.”

Examples of nebulous in a Sentence

These philosophical concepts can be nebulous. made nebulous references to some major changes the future may hold
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
As such, gauging the metrics is a fairly nebulous goal, but Lenovo estimates that 20 minutes of direct sunlight will translate to roughly one hour of video playback. Matthew Buzzi, PCMAG, 2 Mar. 2025 Or, attorneys may be loosely affiliated with a particular group, but the group is not organized as a law firm and any attorney's association with the group is at best nebulous. Jay Adkisson, Forbes, 25 Feb. 2025 The ideas around Kidder seem nebulous at this point — what is her agenda? Rafaela Bassili, Vulture, 20 Feb. 2025 One of his other child costars was a little more nebulous — the mouse brother Stuart Little. Victoria Edel, People.com, 4 Feb. 2025 See All Example Sentences for nebulous

Word History

Etymology

Latin nebulosus misty, from nebula

First Known Use

1674, in the meaning defined at sense 1

Time Traveler
The first known use of nebulous was in 1674

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Cite this Entry

“Nebulous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nebulous. Accessed 14 Mar. 2025.

Kids Definition

nebulous

adjective
neb·​u·​lous ˈneb-yə-ləs How to pronounce nebulous (audio)
1
: of, relating to, or resembling a nebula
2
: not clear or sharp : vague
nebulously adverb
nebulousness noun

More from Merriam-Webster on nebulous

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