'axonal' originates from modern English formation based on the noun 'axon', which itself comes from Greek 'axōn' meaning 'axis' or 'axle'.

'axon' entered scientific English in the 19th century from Greek 'axōn'; the adjective 'axonal' was later formed in English by adding the adjectival suffix '-al' to 'axon'.

Initially based on Greek 'axōn' meaning 'axis', the term came to denote the long projection of a neuron; 'axonal' now means 'pertaining to an axon'.