[ neb-yuh-luh s ]
/ ˈnɛb yə ləs /


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.

Nearby words

  1. nebulize,
  2. nebulizer,
  3. nebulose,
  4. nebulosity,
  5. nebulosus,
  6. nebulously,
  7. nec,
  8. necator,
  9. necatoriasis,
  10. necessarian

Origin of nebulous

1375–1425; late Middle English < Latin nebulōsus full of mist, foggy, cloudy. See nebula, -ous

Related forms Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for nebulous

British Dictionary definitions for nebulous


/ (ˈnɛbjʊləs) /


lacking definite form, shape, or content; vague or amorphousnebulous reasons
of, characteristic of, or resembling a nebula
rare misty or hazy
Derived Formsnebulously, adverbnebulousness, noun

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for nebulous



late 14c., "cloudy, misty," from Latin nebulosus "cloudy, misty, foggy, full of vapor," from nebula (see nebula). The figurative sense of "hazy, vague, formless" is first attested 1831. Astronomical sense is from 1670s. Related: Nebulously; nebulousness.

Online Etymology Dictionary, © 2010 Douglas Harper