adjective

nebulous

/ˈnɛbjʊləs/ · say it: NEB·yuh·lus

vague or ill-defined

In Describing & Comparing

In more detail

1. (adjective) unclear, vague, or ill-defined; not easy to see or understand

2. (adjective) cloudy or hazy in appearance; resembling a cloud or mist

Examples

1. His plans for the future were nebulous and kept changing.
2. The nebulous shape in the sky turned out to be a flock of birds.

How to use nebulous

Nebulous is used in both literal (scientific or poetic) and figurative contexts. The literal sense refers to clouds or mist-like appearance, while the figurative sense describes abstract concepts or ideas that lack clarity and precision. It carries a negative connotation—suggesting something is poorly defined or hard to grasp—and is more formal than casual synonyms like 'fuzzy' or 'vague'.

Common phrases

nebulous concept
nebulous idea
nebulous distinction
nebulous cloud
rather nebulous
somewhat nebulous

Synonyms

vague · unclear · hazy · indistinct · murky

Opposites

clear · distinct · definite

Word family

nebulously (adverb) · nebulousness (noun)

A common mistake

Learners sometimes use nebulous to mean 'mysterious' or 'unknown' in general, but it specifically implies a lack of clarity or poor definition rather than mere obscurity.

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