vacuum tube

American  

noun

1. especially British, vacuum 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.

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vacuum tube British  

noun

1. another name for valve

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vacuum tube Scientific  

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 In other electronic applications, vacuum tubes have largely been replaced by transistors.

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Etymology

Origin of vacuum tube

First recorded in 1775–85

Example Sentences

Yet another is a human-controlled device that uses a vacuum tube to suck up the apples.

From The Wall Street Journal

For a time, it used 5 million volts of electricity to shoot hydrogen nuclei down a vacuum tube at up to 100 million miles an hour.

From The Wall Street Journal

Before silicon, there were vacuum tubes, and before that, there were wires and telegraphs.

From Science Daily

However, the quantum noise that lurks inside the vacuum tubes that encase LIGO's laser beams can alter the timing of the photons in the beams by minutely small amounts.

From Science Daily

In the last century, our capacity to store and process data has soared, with electronics marching from the vacuum tube to the transistor to today’s semiconductor chips.

From Scientific American