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1. slight corneal opacity.
2. an oily preparation for use in a nebulizer.

neb·u·la (nebul.),

, pl.


(neb'yū-lă, -lē),
1. A translucent foglike opacity of the cornea.
2. A class of oily preparations, intended for application by atomization.
3. A spray.
[L. fog, cloud, mist]


n. pl. nebu·lae (-lē′) or nebu·las
1. Astronomy
a. A diffuse cloud 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 light or emits its own light.
b. A galaxy. No longer in technical use.
2. Medicine
a. A cloudy spot on the cornea.
b. A liquid preparation for use in a nebulizer.

neb′u·lar adj.


, pl. nebulae (neb'yū-lă, -lē)
1. A translucent foglike opacity of the cornea.
2. A spray.
[L. fog, cloud, mist]


A cloudy spot on the CORNEA of the eye. A central nebula can severely interfere with clear vision.


Dense, white, corneal opacity caused by scar tissue. A localized leukoma appears as a whitish scar surrounded by normal cornea. A generalized leukoma involves the entire cornea, which appears white, often with blood vessels coursing over its surface. Visual impairment depends on the location and extent of the leukoma. If the opacity is faint, it is called a nebula. Note: also spelt leucoma. See hyperacuity; corneal ulcer.
References in periodicals archive ?
According to NASA, the nebula has an apparent magnitude of 6, which makes it bright enough to be spotted using a pair of binoculars.
- Wireless Health Monitor: Enables network administrators to automatically and continuously monitor and analyze the performance of connected Nebula and NebulaFlex access points.
What are the salient features of Nebula? And how are the corporates in Oman going to benefit from it?
Commenting on introducing Nebula to Oman, Maqbool al-Wahibi,
The colours in the eerie nebula showcase how the nebula is affected by the powerful radiation from the distant star.
Only suspected at 164x, the 12.4-magnitude central star makes a definite appearance against the high-surface-brightness nebula at 234x.
Space Telescope Science Institute and the Caltech/Infrared Processing and Analysis Center (IPAC) has created "the best and most detailed multi-wavelength visualiation yet of the photogenic nebula," said NASA.
Utilizing the powerful web-based Nebula management interface to manage Zyxel's growing family of Cloud-managed access points and Gigabit PoE switches centralizes the IT function and eliminates the requirement for highly-trained IT staff at branch locations.
-Var of animation of Bubble Nebula, or NGC 7635 prepared by NASA
Thomas Madura said that their model indicates that this vast shell of gas and dust has a more complex origin than is generally assumed and for the first time, they have seen evidence suggesting that intense interactions between the stars in the central binary played a significant role in sculpting the nebula we see today.
The Cloud Marketplace will be operated by CGI and branded as the Helix Nebula Marketplace (HNX).
The Lagoon Nebula and the open cluster enmeshed in it are 4,300 light-years distant, considerably closer to us than M22.