When Bell Laboratories wrapped up work on the transistor in 1948, they let 25 employees vote on the name. And for some reason, those stodgy bastards passed up options such as the crystal triode and the iotatron. Sad face.
According to Adafruit, the transistor was originally referred to as a semiconductor triode, but Bell Labs wanted a shorter name. Offering their thoughts on the pros and cons of each name on the ballot, the ballot authors felt crystal triode was misleading (it needed to be piezo-electric for the name to ring true, apparently), and iotatron would not properly distinguish it from gas-filled devices. Of course, they had no issues with transistor as a name. And it was so.
Transistors, of course, went on to become one of the most, if not the most, important component in all of electronics. The little piece of semiconductor material helps amplify signals, or switch those signals on and off. Bell Labs' first transistor could be easily viewed by the naked eye from several feet away. 60 years later, however, billions of them can be packed into a processor not much bigger than your fingertip. [Internet Archive via Adafruit]