noun

a feature or quality belonging typically to a person, place, or thing and serving to identify them.

certain defining characteristics of the school emerge from the study

attribute,feature,quality,essential quality,property,trait,aspect,element,facet,mannerism,manner,habit,custom,way,mark,trademark,hallmark,distinction,idiosyncrasy,peculiarity,quirk,oddity,foible,penchant,proclivity,bent