Definition of tube

• n. - A hollow cylinder, of any material, used for the conveyance of fluids, and for various other purposes; a pipe.
• n. - A telescope.
• n. - A vessel in animal bodies or plants, which conveys a fluid or other substance.
• n. - The narrow, hollow part of a gamopetalous corolla.
• n. - A priming tube, or friction primer. See under Priming, and Friction.
• n. - A small pipe forming part of the boiler, containing water and surrounded by flame or hot gases, or else surrounded by water and forming a flue for the gases to pass through.
• n. - A more or less cylindrical, and often spiral, case secreted or constructed by many annelids, crustaceans, insects, and other animals, for protection or concealment. See Illust. of Tubeworm.
• n. - One of the siphons of a bivalve mollusk.
• v. t. - To furnish with a tube; as, to tube a well.