work out vs tumble

work out is not a noun while tumble is a noun.

Word	Noun	Adjective	Verb	Adverb
work out	No	No	Yes	No
tumble	Yes	No	Yes	No

As verbs, tumble is a hyponym of work out; that is, tumble is a word with a more specific, narrower meaning than work out:

Other hyponyms of work out include limber up, loosen up, warm up, train, strengthen, tone, tone up, press, weight-lift, weightlift.

work out (noun)	tumble (noun)
	an acrobatic feat of rolling or turning end over end
	a sudden drop from an upright position

work out (verb)	tumble (verb)
do physical exercise	do gymnastics, roll and turn skillfully
give a workout to	fall suddenly and sharply
come up with	suffer a sudden downfall, overthrow, or defeat
work out in detail	put clothes in a tumbling barrel, where they are whirled about in hot air, usually with the purpose of drying
find the solution to (a problem or question) or understand the meaning of	understand, usually after some initial difficulty
make a mathematical calculation or computation	throw together in a confused mass
be calculated	fall down, as if collapsing
happen in a certain way, leading to, producing, or resulting in a certain outcome, often well	fall apart
	roll over and over, back and forth
	cause to topple or tumble by pushing
	fly around