Final answer:
Preganglionic fibers are axons from the central neuron to a sympathetic ganglion, while postganglionic fibers are axons from a ganglionic neuron to the target effector.
Step-by-step explanation:
An axon from the central neuron that projects to a sympathetic ganglion is referred to as a preganglionic fiber or neuron, and represents the output from the CNS to the ganglion.
Preganglionic sympathetic fibers are relatively short and myelinated, while postganglionic sympathetic fibers are long and unmyelinated.
The term 'postganglionic neuron' may be used to describe the projection from a ganglion to the target, but typically the term neuron applies to the entire cell.