motor nerve fiber vs efferent neuron

motor nerve fiber and efferent neuron both are nouns.

Word	Noun	Adjective	Verb	Adverb
motor nerve fiber	Yes	No	No	No
efferent neuron	Yes	No	No	No

As nouns, motor nerve fiber and efferent neuron are synonyms defined as:

motor nerve fiber and efferent neuron: a neuron conducting impulses outwards from the brain or spinal cord

Other synonyms of motor nerve fiber include motoneuron, motor neuron.

motor nerve fiber (noun)	efferent neuron (noun)
a neuron conducting impulses outwards from the brain or spinal cord	a neuron conducting impulses outwards from the brain or spinal cord