Aorist

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 Middle Persian, Sanskrit, Armenian, the South Slavic languages, and Georgian also have forms referred to as aorist.

The word comes from Ancient Greek aóristos "indefinite", as the aorist was the unmarked (default) form of the verb, and thus did not have the implications of the imperfective aspect, which referred to an ongoing or repeated situation, or the perfect, which referred to a situation with a continuing relevance; instead it described an action "pure and simple".

Because the aorist was the unmarked aspect in Ancient Greek, the term is sometimes applied to unmarked verb forms in other languages, such as the habitual aspect in Turkish.

In Proto-Indo-European, the aorist appears to have originated as a series of verb forms expressing manner of action. Proto-Indo-European had a three-way aspectual opposition, traditionally called "present", "aorist", and "perfect", which are thought to have been, respectively, imperfective, perfective, and stative (resultant state) aspects. By the time of Classical Greek, this system was maintained largely in independent instances of the non-indicative moods and in the nonfinite forms. But in the indicative, and in dependent clauses with the subjunctive and optative, the aspects took on temporal significance. In this manner, the aorist was often used as an unmarked past tense, and the perfect came to develop a resultative use, which is why the term perfect is used for this meaning in modern languages.

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