Axon comes directly from axon, the Greek word for axle or axis.

In 1845, the Swiss physiologist and comparative anatomist Rudolph Albert von Kölliker (1817-1905) provided the first definitive proof that axons were part of the neuron. 51 years later, in 1898, von Kölliker proposed that these fibers, which form the long axis of the neuron and had come to be called "axis-cylinders", be referred to as "axons" instead. Around the same time, some began using axon as an alternative name for the notocord, but as von Kölliker's axon gained in popularity, axon-as-notocord faded from use.

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