stepper vs high stepper

stepper and high stepper both are nouns.

Word	Noun	Adjective	Verb	Adverb
stepper	Yes	No	No	No
high stepper	Yes	No	No	No

As nouns, stepper and high stepper are synonyms defined as:

stepper and high stepper: a horse trained to lift its feet high off the ground while walking or trotting

stepper (noun)	high stepper (noun)
a horse trained to lift its feet high off the ground while walking or trotting	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 professional dancer