commonality

Short definition from Wiktionary

Noun

1. 1
   The joint possession of a set of attributes or characteristics.
2. 2
   Such a shared attribute or characteristic
3. 3
   A quality that applies to materiel or systems: (a) possessing like and interchangeable parts or characteristics enabling each to be utilized, or operated and maintained in common; (b) having interchangeable repair parts and/or components; (c) applying to consumable items interchangeably equivalent without adjustment.
4. 4
   The common people; the commonalty.