How The Transistor Got Its Name

It’s Labor Day here in the US — a good time to look over the work of folks who have gone before us, and maybe learn something new about our past. So I thought it would be neat to share this Bell Laboratories memo from the spring of 1948. The memo, distributed to the senior technical staff, contained a ballot asking them to choose a name for a new device invented the previous winter – the semiconductor triode. Several options were presented, including my personal favorite, the Iotatron.

In the end, the name “transistor” (“transconductance” + “varistor”) won out over all the others, but it’s still interesting to read the discussion of the other names. I love the note for “solid triode”:

This has the advantage of brevity, and is descriptive in the sense that the device may be explained by the physics of the solid state, and also that the active element is a solid rather than vacuum or gas filled. However, the word “solid” also commonly means sturdy, massive, rugged, or strong, which terms are contradictory to the actual physical characteristics of the unit.

If you’ve ever seen a photo of the first transistor, you’ll agree the secondary meaning of the word “solid” does not apply.

You can read the entire memo here. For simplicity’s sake I uploaded it to my flickr account, but I claim no ownership of the image. I got the original via the Internet Archive’s Wayback Machine.

So what do you think? What would you have called it? Post your suggestions in the comments!

Happy Labor Day!

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  1. I’m rather partial to Crystal Triode. It has a seriously Star Trekish vibe.

  2. @James: Dilithium Crystal Triode!

  3. I love stuff like this. Even though it not required in any work I do, I find myself searching for things like "Where did the 600 ohm standard for audio come from?"
    It is still not very clear, but I found many sources stating that it came from the impedance between suspended telegraph lines.
    I also found a really cool paper that discusses where the 50 ohm standard came from.

  4. From the description of "semiconductor triode" in the memo it appears as though we have the origin of "semiconductor diode" in the same document! Awesome!

  5. Thanks Adafruit! I’ve always wondered how the smart guys who invented the transistor got the name so wrong. I knew where the name came from and have always wondered about "varistor" in the name. The transistor is NOT a variable resistor. A resistor passes current in either direction, the transistor only passes current in one direction. Ten years after Bardeen et. al., the FET (Field Effect Transistor) was invented and IS a true varistor. Since that name caused confusion using the name of the bipolar device, it finally became the MOS (Metal Oxide Semiconductor), and CMOS (Complementary MOS) logic pushed the transistor out of digital circuitry applications. It would be in the interest of accuracy to remove "varistor" from the name of the bipolar device. I would fill in (other suggestion) with Silicon Triode. But then, the first transistors were Germanium. . . . Oh well, now we know that the inaccurate name of the transistor was the result of a popularity poll!

  6. @Bob: The term “varistor”, as used in the name “transistor”, does not refer to the device behaving as a variable resistor. Rather it refers to the non-linear V-I characteristic of the BJT, which is also a characteristic of varistors.

    The name “transistor” is really quite descriptive of the device in question: it tells you that you can control an output current with an input voltage (transconductance), and that the relationship will be non-linear (varistor). The fact that it works in only one direction is important too, but ultimately you have to to make some sacrifices for brevity.

  7. Transconductance varistor? A long time back I was told that it stood for “transfer resistor”.

  8. Do you know that it is almost impossible to post because of your human prover works poorly on an iOS device.

  9. @james – it seems you were able to post that comment?

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