centralization vs centralisation

centralization and centralisation both are nouns.

Word	Noun	Adjective	Verb	Adverb
centralization	Yes	No	No	No
centralisation	Yes	No	No	No

As nouns, centralization and centralisation are synonyms defined as:

centralization and centralisation: the act of consolidating power under a central control

As nouns, centralization and centralisation are synonyms defined as:

centralization (noun)	centralisation (noun)
the act of consolidating power under a central control	the act of consolidating power under a central control
gathering to a center	gathering to a center