Aorist (/ˈeɪ.ərᵻst/; abbreviated AOR) verb forms usually express perfective aspect and refer to past events, similar to a preterite. Ancient Greek grammar had the aorist form, and the grammars of other Indo-European languages and languages influenced by the Indo-European grammatical tradition, such as Sanskrit, Armenian, the South Slavic languages, and Georgian also have forms referred to as aorist.