A giant pyramidal neuron with a soma in layer Vb of the primary motor cortex that sends its axons down the spinal cord via the corticospinal tract, either synapsing directly with alpha motor neurons, or targeting interneurons in the spinal cord. In humans, Betz cells are the largest known in the central nervous system. [ http://dx.doi.org/10.1101/2020.03.31.016972 http://en.wikipedia.org/wiki/Betz_cell&oldid=977472330 ]