What does "barrel" mean?

Barrel: The quantity which constitutes a full barrel. This varies for different articles and also in different places for the same article, being regulated by custom or by law. A barrel of wine is 31 3. A solid drum, or a hollow cylinder or case; as, the barrel of a windlass; the barrel of a watch, within which the spring is coiled.

Additional senses

  1. 2.A metallic tube, as of a gun, from which a projectile is discharged. Knight.
  2. 3.A jar. [Obs.] 1 Kings xvii.
  3. 4.6. (Zoöl.) The hollow basal part of a feather. Barrel bulk (Com.), a measure equal to five cubic feet, used in estimating capacity, as of a vessel for freight. -- Barrel drain (Arch.), a drain in the form of a cylindrical tube. -- Barrel of a boiler, the cylindrical part of a boiler, containing the flues. -- Barrel of the ear (Anat.), the tympanum, or tympanic cavity. -- Barrel organ, an instrument for producing music by the action of a revolving cylinder. -- Barrel vault. See under Vault.
  4. 5.To put or to pack in a barrel or barrels.

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