sectionalize

From sectional +‎ -ize.

sectionalize (third-person singular simple present sectionalizes, present participle sectionalizing, simple past and past participle sectionalized)

1. (transitive) To divide into sections.
   • 1886-90, John G. Nicolay and John Hay, Abraham Lincoln: A History

     On the whole, the principal results of the struggle were, to sectionalize parties more completely, ripen Southern sentiment towards secession, and combine wavering voters in the free-States in support of Republican doctrines.

• sectionalization