motoneuron vs nerve cell

motoneuron and nerve cell both are nouns.

Word	Noun	Adjective	Verb	Adverb
motoneuron	Yes	No	No	No
nerve cell	Yes	No	No	No

As nouns, nerve cell is a hypernym of motoneuron; that is, nerve cell is a word with a broader meaning than motoneuron:

motoneuron: a neuron conducting impulses outwards from the brain or spinal cord
nerve cell: a cell that is specialized to conduct nerve impulses

Other hypernyms of motoneuron include neuron.

motoneuron (noun)	nerve cell (noun)
a neuron conducting impulses outwards from the brain or spinal cord	a cell that is specialized to conduct nerve impulses