Dewar flask
- noun
- /ˈdjuːər flæsk/
- Specialized
:
frasco Dewar
- For the experiment, he carefully transferred helium gas into a Dewar flask to prevent it from warming up.
Examples
-
Starlight enters through a small window in the side of the Dewar flask and raises the temperature of the bolometer.
Academic text (1991) -
The scientist stored the liquid nitrogen in a Dewar flask to keep it at a very low temperature.
-
A series of laboratory trials using chicken manure in Dewar flasks only resulted in temperatures of 117 degrees Fahrenheit.
Academic text (1999) -
She used a Dewar flask to maintain the temperature of the liquid oxygen needed for her research.
Synonyms
1
7.8
A container that keeps very cold liquids like liquid nitrogen or helium cold
A container that keeps drinks hot or cold for a long time
A container with two walls and empty space between them that keeps drinks hot or cold
A container that keeps drinks hot or cold for a long time
How Insulating
Surface Forms
Morphology
A B1 learner who knows 'flask' will correctly infer this is a type of container, but the constituent 'Dewar' is a proper name and does not transparently convey the crucial properties (vacuum insulation, use for very cold liquids) unless the learner already knows the eponym. Because the specific technical meaning (vacuum‑sealed, for extremely cold liquids) is not derivable from the parts alone, the expression is partially but not fully transparent.
Etymology
Dewar flask is named after the scientist James Dewar, who made a glass flask with two walls and an empty space, a 'vacuum', between them to stop heat moving. That's why a Dewar flask is used to keep liquids very cold.