nebulous

adjective

1. hazy, vague, indistinct, or confused: a nebulous recollection of the meeting; a nebulous distinction between pride and conceit.
2. cloudy or cloudlike.
3. of or resembling a nebula or nebulae in deep space; nebular.

adjective

1. lacking definite form, shape, or content; vague or amorphousnebulous reasons
2. of, characteristic of, or resembling a nebula
3. rare misty or hazy

adj.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.