- The definition of a nebula is a cloud of gas and dust in outer space.
A mass of dust in the sky that reflects light and appears as darkness in the sky may be an example of a nebula.
The Orion Nebula.Licensed from iStockPhoto
- a cloud of interstellar gas or dust: formerly, applied to any hazy, distant celestial object, as a star cluster or an external galaxy
- a small, cloudy opacity on the cornea
- a liquid preparation used as a spray
Origin: ModL from L, vapor, fog, mist from Indo-European base an unverified form nebh-, moist, vapor, cloud from source Glassical Greek nephos, nephelē, cloud, Old English nifol, mist, darkness
- nebular adjective
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noun pl. neb·u·lae or neb·u·las
- Astronomy a. A diffuse mass of interstellar dust or gas or both, visible as luminous patches or areas of darkness depending on the way the mass absorbs or reflects incident radiation.b. See galaxy.
- Pathology a. A cloudy spot on the cornea.b. Cloudiness in the urine.
- A liquid medication applied by spraying.
Origin: Middle English nebule, cloud, mist, from Latin nebula; see nebh- in Indo-European roots.
- nebˈu·lar adjective
nebula - Cultural Definition
nebula - Medical Definition
noun pl. neb·u·las or neb·u·lae
- A faint, foglike opacity of the cornea.
- A class of oily preparations for use in a nebulizer.
nebula - Science Definition
Plural nebulae nebulae or nebulas
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