| nebula | Origin: L, mist, cloud; akin to Gr, cloud, mist, G. Nebel mist, OHG. Nebul, D. Nevel, Skr. Nabhas cloud, mist. Cf. Nebule. 1. <astronomy> A faint, cloudlike, self-luminous mass of matter situated beyond the solar system among the stars. True nebulae are gaseous; but very distant star clusters often appear like them in the telescope. 2. <medicine> A white spot or a slight opacity of the cornea. A cloudy appearance in the urine. Source: Websters Dictionary (01 Mar 1998) |
|---|---|
| nebular | Of or pertaining to nebulae; of the nature of, or resembling, a nebula. Nebular hypothesis, an hypothesis to explain the process of formation of the stars and planets, presented in various forms by Kant, Herschel, Laplace, and others. As formed by Laplace, it supposed the matter of the solar system to have existed originally in the form of a vast, diffused, revolving nebula, which, gradually cooling and contracting, threw off, in obedience to mechanical and physical laws, succesive rings of matter, from which subsequently, by the same laws, were produced the several planets, satellites, and other bodies of the system. The phrase may indicate any hypothesis according to which the stars or the bodies of the solar system have been evolved from a widely diffused nebulous form of matter. Source: Websters Dictionary (01 Mar 1998) |
| nebularine | A toxic nucleoside isolated from the mushroom Agaricus nebularis and from Streptomyces sp. Synonym: 9-beta-ribofuranosylpurine, purine ribonucleoside, ribosylpurine. (05 Mar 2000) |