nebulous
Americanadjective
-
hazy, vague, indistinct, or confused.
a nebulous recollection of the meeting; a nebulous distinction between pride and conceit.
-
cloudy or cloudlike.
-
of or resembling a nebula or nebulae in deep space; nebular.
adjective
-
lacking definite form, shape, or content; vague or amorphous
nebulous reasons
-
of, characteristic of, or resembling a nebula
-
rare misty or hazy
Other Word Forms
- nebulously adverb
- nebulousness noun
- nonnebulous adjective
- nonnebulously adverb
- nonnebulousness noun
- quasi-nebulous adjective
- quasi-nebulously adverb
Etymology
Origin of nebulous
First recorded in 1375–1425; late Middle English, from Latin nebulōsus “full of mist, foggy, cloudy,” from nebul(a) “cloud, mist, vapor” ( nebula ) + -ōsus -ous
Explanation
Something that's nebulous is clouded or hazy. When you walk through the woods on a foggy morning, the trees may all have a mysterious, nebulous look to them. When you fly in a plane on an overcast day, the land below you looks nebulous and indistinct. You can also use nebulous in a more figurative way, to describe vague ideas or fuzzy concepts. Nebulous comes from the Latin nebulosus, "cloudy, misty, or foggy." Its root is nebula, which is "vapor or fog" in Latin and was adopted by astronomers in the 1700s to mean "a cloud of gas and dust in outer space."
Vocabulary lists containing nebulous
To Kill a Mockingbird
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The Great Gatsby
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1984
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
No longer will his clean ball-striking be impaired by nebulous thinking.
From BBC • Apr. 7, 2026
For many American families, saving for college is a daunting and nebulous task.
From MarketWatch • Apr. 1, 2026
Quite often, while these U-turns shake up markets, they remain nebulous in terms of actual deals.
From Barron's • Mar. 23, 2026
By midday Friday, it remained unclear when the partial shutdown would end, as lawmakers left Washington for a security conference in Munich and progress between Democratic and White House negotiators remained nebulous.
From Los Angeles Times • Feb. 13, 2026
Livermore’s nebulous mandate was an ideal fit for Lawrence’s scheme.
From "Big Science" by Michael Hiltzik
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
