Definition of "flask"

A narrow-necked vessel of metal or glass, used for various purposes; as of sheet metal, to carry gunpowder in; or of wrought iron, to contain quicksilver; or of glass, to heat water in, etc.  examples

A container used to discreetly carry a small amount of a hard alcoholic beverage; a pocket flask.  examples

(sciences) Laboratory glassware used to hold larger volumes than test tubes, normally having a narrow mouth of a standard size which widens to a flat or spherical base.  examples

(engineering) A container for holding a casting mold, especially for sand casting molds.  examples

A bed in a gun carriage.  examples

(dentistry) To invest a denture in a flask so as to produce a sectional mold.  examples