noun conduit consisting of a long hollow object (usually cylindrical) used to hold and conduct objects or liquids or gases.
— synonyms: tubing
noun electronic device consisting of a system of electrodes arranged in an evacuated glass or metal envelope.
— synonyms: vacuum_tube, thermionic_vacuum_tube, thermionic_tube, electron_tube, thermionic_valve
noun a hollow cylindrical shape.
— synonyms: pipe
noun (anatomy) any hollow cylindrical body structure.
— synonyms: tube-shaped_structure
noun an electric railway operating below the surface of the ground (usually in a city).
— synonyms: metro, underground, subway_system, subway
Examples
“A tube of toothpaste.”
“I took the tube to Waterloo and walked the rest of the way.”
“Are you just going to sit around all day and watch the tube?”