What does "regionality" mean?

The property of being regional.

Regionality

Common synonyms include: geographic origin, geographic specificity, local flavor, origin locality, regional character, regional difference.

noun

noun ·Rare ·Advanced level

Noun

1
The property of being regional. countable, uncountable
"The party's regionality prevented it from winning a national election."
2
The property of being of, or pertaining to, a specific region or district. wordnet
3
The property of being of, or pertaining to, a large geographic region. wordnet

"The party's regionality prevented it from winning a national election."

From regional + -ity.