groundbreaking vs innovational

groundbreaking is a noun but innovational is not a noun.

Word	Noun	Adjective	Verb	Adverb
groundbreaking	Yes	Yes	No	No
innovational	No	Yes	No	No

As adjectives, groundbreaking and innovational are synonyms defined as:

groundbreaking and innovational: being or producing something like nothing done or experienced or created before

Other synonyms of groundbreaking include innovative.

groundbreaking (noun)	innovational (noun)
the ceremonial breaking of the ground to formally begin a construction project

groundbreaking (adjective)	innovational (adjective)
being or producing something like nothing done or experienced or created before	being or producing something like nothing done or experienced or created before