Definition

1. Noun:
   • A vacuum flask designed for scientific use: A "dewar" is a specialized container with double walls and a vacuum between them, used to store cryogenic liquids like liquid air or helium at very low temperatures for extended periods with minimal evaporation.
   • A person, Sir James Dewar: A "Dewar" can refer to the Scottish chemist and physicist Sir James Dewar (1842–1923), who invented the vacuum flask that bears his name and conducted pioneering work in cryogenics.

Usage Examples

• Noun (Container):
  • The laboratory technician carefully poured the liquid nitrogen into the dewar.
  • For the experiment to work, we need to keep the samples in a dewar filled with liquid helium.
• Noun (Person):
  • Dewar's research laid the groundwork for modern low-temperature physics.
  • The invention of the vacuum flask is credited to Dewar.

Advanced Usage

• "Dewar flask": This is the full name for the specific type of vacuum bottle invented by Sir James Dewar. While "dewar" is commonly used alone in scientific contexts to mean the container, "Dewar flask" specifies the original design.
  • The original Dewar flask was a silvered glass vessel.

Variants and Related Words

• Dewar flask (n): The full term for the insulating vessel.
• Cryogenic dewar (n): A dewar specifically designed for storing cryogenic liquids.
• Vacuum flask (n): A more general term for any double-walled, evacuated container used for thermal insulation; a "dewar" is a type of vacuum flask for scientific use.

Synonyms

• Vacuum flask (for the container sense).
• Cryogenic container (for the container sense).
• Insulated vessel (for the container sense).

Related Idioms or Phrases

• The term "dewar" is primarily a technical noun and is not typically used in idiomatic expressions.

Noun

1. Scottish chemist and physicist noted for his work in cryogenics and his invention of the Dewar flask (1842-1923)
2. vacuum flask that holds liquid air or helium for scientific experiments