vertical union vs labor union

vertical union and labor union both are nouns.

Word	Noun	Adjective	Verb	Adverb
vertical union	Yes	No	No	No
labor union	Yes	No	No	No

As nouns, labor union is a hypernym of vertical union; that is, labor union is a word with a broader meaning than vertical union:

vertical union: a labor union that admits all workers in a given industry irrespective of their craft
labor union: an organization of employees formed to bargain with the employer

Other hypernyms of vertical union include brotherhood, trade union, trades union, union.

vertical union (noun)	labor union (noun)
a labor union that admits all workers in a given industry irrespective of their craft	an organization of employees formed to bargain with the employer