stepper vs stepping motor

stepper and stepping motor both are nouns.

Word	Noun	Adjective	Verb	Adverb
stepper	Yes	No	No	No
stepping motor	Yes	No	No	No

As nouns, stepper and stepping motor are synonyms defined as:

stepper and stepping motor: a motor (especially an electric motor) that moves or rotates in small discrete steps

stepper (noun)	stepping motor (noun)
a horse trained to lift its feet high off the ground while walking or trotting	a motor (especially an electric motor) that moves or rotates in small discrete steps
a motor (especially an electric motor) that moves or rotates in small discrete steps
a professional dancer