vertical combination vs vertical integration

vertical combination and vertical integration both are nouns.

Word	Noun	Adjective	Verb	Adverb
vertical combination	Yes	No	No	No
vertical integration	Yes	No	No	No

As nouns, vertical combination and vertical integration are synonyms defined as:

vertical combination and vertical integration: absorption into a single firm of several firms involved in all aspects of a product's manufacture from raw materials to distribution

vertical combination (noun)	vertical integration (noun)
absorption into a single firm of several firms involved in all aspects of a product's manufacture from raw materials to distribution	absorption into a single firm of several firms involved in all aspects of a product's manufacture from raw materials to distribution