showjumping vs stadium jumping

showjumping and stadium jumping both are nouns.

Word	Noun	Adjective	Verb	Adverb
showjumping	Yes	No	No	No
stadium jumping	Yes	No	No	No

As nouns, showjumping and stadium jumping are synonyms defined as:

showjumping and stadium jumping: riding horses in competitions over set courses to demonstrate skill in jumping over obstacles

showjumping (noun)	stadium jumping (noun)
riding horses in competitions over set courses to demonstrate skill in jumping over obstacles	riding horses in competitions over set courses to demonstrate skill in jumping over obstacles