equestrian vs horseback riding

equestrian and horseback riding both are nouns.

Word	Noun	Adjective	Verb	Adverb
equestrian	Yes	Yes	No	No
horseback riding	Yes	No	No	No

equestrian (noun)	horseback riding (noun)
a person skilled in equitation	travel by being carried on horseback
	the sport of sitting on the back of a horse while controlling its movements

equestrian (adjective)	horseback riding (adjective)
of or relating to or featuring horseback riding
of or relating to or composed of knights