. [ After Sir James Dewar, British physicist. ] 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. [ Webster 1913 Suppl. +PJC ]

n. [ AS. flasce, flaxe; akin to D. flesch, OHG. flasca, G. flasche, Icel. & Sw. flaska, Dan. flaske, OF. flasche, LL. flasca, flasco; of uncertain origin; cf. L. vasculum, dim. of vas a vessel, Gr. fla`skh, fla`skwn, fla`skion. Cf. Flagon, Flasket. ] 1. A small bottle-shaped vessel for holding fluids; as, a flask of oil or wine. [ 1913 Webster ]

2. 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. [ 1913 Webster ]

3. A bed in a gun carriage. [ Obs. ] Bailey. [ 1913 Webster ]

4. (Founding) The wooden or iron frame which holds the sand, etc., forming the mold used in a foundry; it consists of two or more parts; viz., the cope or top; sometimes, the cheeks, or middle part; and the drag, or bottom part. When there are one or more cheeks, the flask is called a three part flask, four part flask, etc. [ 1913 Webster ]

Erlenmeyer flask, a thin glass flask, flat-bottomed and cone-shaped to allow of safely shaking its contents laterally without danger of spilling; -- so called from Erlenmeyer, a German chemist who invented it. --
Florence flask. [ From Florence in Italy. ] (a) Same as Betty, n., 3. (b) A glass flask, round or pear-shaped, with round or flat bottom, and usually very thin to allow of heating solutions. --
Pocket flask, a kind of pocket dram bottle, often covered with metal or leather to protect it from breaking. [ 1913 Webster ]

n. [ Cf. W. fflasged a vessel of straw or wickerwork, fflasg flask, basket, and E. flask. ] 1. A long, shallow basket, with two handles. [ Eng. ] [ 1913 Webster ]

In which they gathered flowers to fill their flasket. Spenser. [ 1913 Webster ]

2. A small flask. [ 1913 Webster ]

3. A vessel in which viands are served. [ Obs. ] Pope. [ 1913 Webster ]

n. A small portable flask, usually made of metal, used to hold liquor.
Syn. -- pocket flask. [ WordNet 1.5 ]

n. A flask in which gunpowder is carried, having a charging tube at the end. [ 1913 Webster ]