Definitions for "Dewar flask"
A double-walled glass vessel for holding liquid air, liquid nitrogen, etc., having the space between the walls exhausted so as to prevent conduction of heat, and sometimes having the glass silvered to prevent absorption of radiant heat; -- called also, according to the particular shape, Dewar bulb, Dewar tube, etc.
du Er flaesk] A vacuum-insulated sealable container with a heat reflective inner surface. A dewar containing a cryogen (a low temperature producing substance) is known as a cryostat.
vacuum flask that holds liquid air or helium for scientific experiments