vacuum tube

noun

1. alsocalledcomma especially British, vacuum valve. an electron tube from which almost all air or gas has been evacuated: formerly used extensively in radio and electronics.
2. a sealed glass tube with electrodes and a partial vacuum or a highly rarefied gas, used to observe the effects of a discharge of electricity passed through it.

vacuum tube

noun

1. another name for valve

vacuum tube

1. An electron tube from which all air has been removed. The vacuum ensures transparency inside the tube for electric fields and moving electrons. Most electron tubes are vacuum tubes; cathode-ray tubes, which include television picture tubes and other video display tubes, are the most widely used vacuum tubes. In other electronic applications, vacuum tubes have largely been replaced by transistors.

Word History and Origins

Origin of vacuum tube¹

First recorded in 1775–85

Example Sentences

The heart of your microwave is called a magnetron—a bulky component made of a vacuum tube and two magnets.

From Popular-Science

We covered the revolution in computing that has transformed science and society from the era of vacuum tubes.

From Science News

It was only a matter, he said, of transferring a man's habit patterns from brain cells to vacuum-tube cells.

From Project Gutenberg

The luminous phenomena are very similar to those seen when a current of electricity is passed through a vacuum tube.

From Project Gutenberg

An interesting vacuum tube is made which has no electrodes, but contains a quantity of mercury.

From Project Gutenberg

These are met with in barometers, spray arresters, and filter pumps, in condensers and some forms of vacuum tube.

From Project Gutenberg

A form of vacuum tube which has proved very successful in the author's hands is sketched in Fig. 38.

From Project Gutenberg