rotor vs armature

rotor and armature both are nouns.

Word	Noun	Adjective	Verb	Adverb
rotor	Yes	No	No	No
armature	Yes	No	No	No

As nouns, armature is a hypernym of rotor; that is, armature is a word with a broader meaning than rotor:

rotor: the rotating armature of a motor or generator
armature: coil in which voltage is induced by motion through a magnetic field

rotor (noun)	armature (noun)
rotating mechanism consisting of an assembly of rotating airfoils	coil in which voltage is induced by motion through a magnetic field
the rotating armature of a motor or generator
the revolving bar of a distributor