nebula
/'nebjulə/
Học thuậtThân thiện
Definition
- Noun:
- (Astronomy) An immense cloud of gas (mainly hydrogen) and dust in interstellar space. A nebula is a vast, diffuse cloud in space, often the birthplace of stars or the remnants of a star's death.
- (Pathology) A faint cloudy spot on the cornea. In medicine, a nebula is a slight opacity or scar on the cornea of the eye, causing a minor cloudiness in vision.
- (Pharmacy) A medicinal liquid preparation intended for use in an atomizer. This is a specialized term for a fine spray or mist used for inhalation.
- Cloudiness of the urine. An archaic or highly specialized medical term for a cloudy appearance in urine.
Usage Examples
- Astronomy:
- The Orion Nebula is a stellar nursery where new stars are forming.
- Through the telescope, we observed a beautiful glowing nebula.
- Pathology:
- The ophthalmologist noted a small nebula on the patient's cornea from an old injury.
- Pharmacy:
- The doctor prescribed a saline nebula for the patient's respiratory therapy.
Advanced Usage
- "Planetary nebula": A specific type of nebula formed from the outer layers of a dying, low-mass star, often appearing as a glowing shell of gas.
- The Ring Nebula is a famous example of a planetary nebula.
- "Diffuse nebula": A broad category of nebulae that are extended and lack well-defined boundaries, often illuminated by nearby stars.
- Emission nebulae and reflection nebulae are types of diffuse nebulae.
Variants and Related Words
- Nebulae (n): The standard plural form of nebula.
- The Hubble Space Telescope has captured images of countless nebulae.
- Nebular (adj): Relating to or resembling a nebula.
- The nebular hypothesis is a theory for the formation of the solar system.
- Nebulizer (n): A device that converts a liquid medicine into a fine mist (a nebula) for inhalation. This is the common modern term derived from the pharmaceutical sense.
- She uses a nebulizer to administer her asthma medication.
Synonyms
- Astronomy: Cloud, interstellar cloud, galactic cloud.
- Pathology: Corneal opacity, corneal scar, leucoma (a more dense opacity).
Notes on Meaning
- The primary and most common modern usage is the astronomical meaning. When people say "nebula," they are almost always referring to the cosmic clouds.
- The medical (pathology) meaning is technical and less common in everyday language.
- The pharmaceutical meaning is largely historical or highly specialized; the device is now almost exclusively called a nebulizer.
- The urine cloudiness meaning is obsolete.
Noun
- (pathology) a faint cloudy spot on the cornea
- an immense cloud of gas (mainly hydrogen) and dust in interstellar space
- cloudiness of the urine
- a medicinal liquid preparation intended for use in an atomizer