1 cloudlike.
2 a formless, clouded. b hazy, indistinct, vague (put forward a few nebulous ideas).
3 Astron. of or like a nebula or nebulae.
Phrases and idioms:
nebulous star a small cluster of indistinct stars, or a star in a luminous haze.
Derivatives:
nebulosity n. nebulously adv. nebulousness n.
Etymology: ME f. F neacutebuleux or L nebulosus (as NEBULA)
Useful english dictionary. 2012.