jump on vs jump

jump on is not a noun while jump is a noun.

Word	Noun	Adjective	Verb	Adverb
jump on	No	No	Yes	No
jump	Yes	No	Yes	No

jump on (noun)	jump (noun)
	the act of jumping; propelling yourself off the ground
	a sudden involuntary movement
	descent with a parachute
	(film) an abrupt transition from one scene to another
	an abrupt transition
	a sudden and decisive increase

jump on (verb)	jump (verb)
get up on the back of	increase suddenly and significantly
	rise in rank or status
	go back and forth; swing back and forth between two states or conditions
	pass abruptly from one state or topic to another
	bypass
	make a sudden physical attack on
	enter eagerly into
	move forward by leaps and bounds
	cause to jump or leap
	move or jump suddenly, as if in surprise or alarm
	run off or leave the rails
	start (a car engine whose battery is dead) by connecting it to another car's battery
	jump down from an elevated point
	jump from an airplane and descend with a parachute
	be highly noticeable