|Region||Eastern Iranian plateau|
|Era||Iron Age, Late Bronze Age|
|No native script
Written in Pahlavi script (Avestan alphabet, independent ad-hoc development)
Gujarati script used by the Indian Zoroastrian community
Yasna 28.1, Ahunavaiti Gatha (Bodleian MS J2)
Avestan //, formerly also known as "Zend" , is an Aryan, East Iranian language known only from its use as the language of Zoroastrian scripture, i.e. the Avesta, from which it derives its name. Its area of composition comprised Arachosia/Sīstān, Hyrcania , Herat, Merv and Bactria,  which in modern-day are part of Turkmenistan, Iran, Afghanistan and Pakistan.
Avestan's status as a sacred language has ensured its continuing use for new compositions long after the language had ceased to be a living language. It is closely related to Vedic Sanskrit, the oldest preserved Indo-Aryan language.
"Avestan, which is associated with northeastern Iran, and Old Persian, which belongs to the southwest, together constitute what is called Old Iranian."[f 1] The Old Iranian language group is a branch of the Indo-Iranian language group. Iranian languages are traditionally classified as "eastern" or "western", and within this framework Avestan is classified as eastern. But this distinction is of limited meaning for Avestan, as the linguistic developments that later distinguish Eastern from Western Iranian had not yet occurred. Avestan does not display some typical (South-)Western Iranian innovations already visible in Old Persian, and so in this sense, "eastern" only means "non-western". That is not to say that Avestan does not display any characteristic innovations of its own – e.g., the sibilant pronunciation of the consonant in aša, corresponding to original /rt/ that is preserved in the Old Persian form (arta), as well as Sanskrit (rta).
Christopher I. Beckwith claims, in Empires of the Silk Road, that Avestan is an Indo-Aryan language, with the Iranian linguistic traits found in the Avesta having been introduced by oral transmission among Iranian language speakers.
Forms and stages of development
The Avestan language is attested in roughly two forms, known as "Old Avestan" (or "Gathic Avestan") and "Younger Avestan". Younger Avestan did not evolve from Old Avestan; the two differ not only in time, but are also different dialects. Every Avestan text, regardless of whether originally composed in Old or Younger Avestan, underwent several transformations. Karl Hoffmann traced the following stages for Avestan as found in the extant texts. In roughly chronological order:
- The natural language of the composers of the Gathas, the Yasna Haptanghaiti, the four sacred prayers (Y. 27 and 54).
- Changes precipitated by slow chanting
- Changes to Old Avestan due to transmission by native speakers of Younger Avestan
- The natural language of the composers of grammatically correct Younger Avestan texts
- Deliberate changes introduced through "standardization"
- Changes introduced by transfer to regions where Avestan was not spoken
- Adaptions/Translations of portions of texts from other regions
- Composition of ungrammatical late Avestan texts
- Phonetic notation of the Avestan texts in the Sasanian archetype
- Post-Sasanian deterioration of the written transmission due to incorrect pronunciation
- Errors and corruptions introduced during copying
Many phonetic features cannot be ascribed with certainty to a particular stage since there may be more than one possibility. Every phonetic form that can be ascribed to the Sasanian archetype on the basis of critical assessment of the manuscript evidence must have gone through the stages mentioned above so that "Old Avestan" and "Young Avestan" really mean no more than "Old Avestan and Young Avestan of the Sasanian period."
The script used for writing Avestan developed during the 3rd or 4th century AD. By then the language had been extinct for many centuries, and remained in use only as a liturgical language of the Avesta canon. As is still the case today, the liturgies were memorized by the priesthood and recited by rote.
The script devised to render Avestan was natively known as Din dabireh "religion writing". It has 53 distinct characters and is written right-to-left. Among the 53 characters are about 30 letters that are – through the addition of various loops and flourishes – variations of the 13 graphemes of the cursive Pahlavi script (i.e. "Book" Pahlavi) that is known from the post-Sassanian texts of Zoroastrian tradition. These symbols, like those of all the Pahlavi scripts, are in turn based on Aramaic script symbols. Avestan also incorporates several letters from other writing systems, most notably the vowels, which are mostly derived from Greek minuscules. A few letters were free inventions, as were also the symbols used for punctuation. Also, the Avestan alphabet has one letter that has no corresponding sound in the Avestan language; the character for /
l/ (a sound that Avestan does not have) was added to write Pazend texts.
Avestan script is alphabetic, and the large number of letters suggests that its design was due to the need to render the orally recited texts with high phonetic precision. The correct enunciation of the liturgies was (and still is) considered necessary for the prayers to be effective.
The Zoroastrians of India, who represent one of the largest surviving Zoroastrian communities worldwide, also transcribe Avestan in Brahmi-based scripts. This is a relatively recent development first seen in the ca. 12th century texts of Neryosang Dhaval and other Parsi Sanskritist theologians of that era, and which are roughly contemporary with the oldest surviving manuscripts in Avestan script. Today, Avestan is most commonly typeset in Gujarati script (Gujarati being the traditional language of the Indian Zoroastrians). Some Avestan letters with no corresponding symbol are synthesized with additional diacritical marks, for example, the /z/ in zaraϑuštra is written with /j/ + dot below.
Avestan has retained voiced sibilants, and has fricative rather than aspirate series. There are various conventions for transliteration of Dīn Dabireh, the one adopted for this article being:
- a ā ə ə̄ e ē o ō å ą i ī u ū
- k g γ x xʷ č ǰ t d δ ϑ t̰ p b β f
- ŋ ŋʷ ṇ ń n m y w r s z š ṣ̌ ž h
The glides y and w are often transcribed as ii and uu, imitating Dīn Dabireh orthography.
|Nasal||m /m/||n /n/||ń [ɲ]||ŋ /ŋ/||ŋʷ /ŋʷ/|
|Plosive||p /p/||b /b/||t /t/||d /d/||č /tʃ/||ǰ /dʒ/||k /k/||g /ɡ/|
|Fricative||f /ɸ/||β /β/||ϑ /θ/||δ /ð/||s /s/||z /z/||š /ʃ/||ž /ʒ/||x /x/||γ /ɣ/||xʷ /xʷ/||h /h/|
|Approximant||y /j/||w /w/|
According to Beekes, [ð] and [ɣ] are allophones of /θ/ and /x/ respectively (in Old Avestan).
|Close||i /i/||ī /iː/||u /u/||ū /uː/|
|Mid||e /e/||ē /eː/||ə /ə/||ə̄ /əː/||o /o/||ō /oː/|
||ā /aː/||å /ɒː/|
|Case||"normal" endings||a-stems: (masc. neut.)|
|Nominative||-s||-ā||-ō (-as), -ā||-ō (yasn-ō)||-a (vīr-a)||-a (-yasna)|
|Vocative||–||-ā||-ō (-as), -ā||-a (ahur-a)||-a (vīr-a)||-a (yasn-a), -ånghō|
|Accusative||-əm||-ā||-ō (-as, -ns), -ā||-əm (ahur-əm)||-a (vīr-a)||-ą (haom-ą)|
|Instrumental||-ā||-byā||-bīš||-a (ahur-a)||-aēibya (vīr-aēibya)||-āiš (yasn-āiš)|
|Dative||-ē||-byā||-byō (-byas)||-āi (ahur-āi)||-aēibya (vīr-aēibya)||-aēibyō (yasn-aēibyō)|
|Ablative||-at||-byā||-byō||-āt (yasn-āt)||-aēibya (vīr-aēibya)||-aēibyō (yasn-aēibyō)|
|Genitive||-ō (-as)||-å||-ąm||-ahe (ahur-ahe)||-ayå (vīr-ayå)||-anąm (yasn-anąm)|
|Locative||-i||-ō, -yō||-su, -hu, -šva||-e (yesn-e)||-ayō (zast-ayō)||-aēšu (vīr-aēšu), -aēšva|
||Gujarati script approximation
|ahiiā. yāsā. nəmaŋhā. ustānazastō.1 rafəδrahiiā.maniiə̄uš.2 mazdā.3 pouruuīm.4 spəṇtahiiā. aṣ̌ā. vīspə̄ṇg.5 š́iiaoϑanā.6vaŋhə̄uš. xratūm.7 manaŋhō. yā. xṣ̌nəuuīṣ̌ā.8 gə̄ušcā. uruuānəm.9:: (du. bār)::ahiiā. yāsā. nəmaŋhā. ustānazastō. rafəδrahiiā.maniiə̄uš. mazdā. pouruuīm. spəṇtahiiā. aṣ̌ā. vīspə̄ṇg. š́iiaoϑanā.vaŋhə̄uš. xratūm. manaŋhō. yā. xṣ̌nəuuīṣ̌ā. gə̄ušcā. uruuānəm.::
||અહીઆ। યાસા। નામંગહા। ઉસ્તાનજ઼સ્તો।૧ રફ઼ાધરહીઆ।મનીઆઉસ્̌।૨ મજ઼્દા।૩ પોઉરુઉઈમ્।૪ સ્પાણ્તહીઆ। અષ્̌આ। વીસ્પાણ્ગ્।૫ સ્̌́ઇઇઅઓથઅના।૬વંગહાઉસ્̌। ક્સરતૂમ્।૭ મનંગહો। યા। ક્સષ્̌નાઉઉઈષ્̌આ।૮ ગાઉસ્̌ચા। ઉરુઉઆનામ્।૯:: (દુ। બાર્)::અહીઆ। યાસા। નામંગહા। ઉસ્તાનજ઼સ્તો। રફ઼ાધરહીઆ।મનીઆઉસ્̌। મજ઼્દા। પોઉરુઉઈમ્। સ્પાણ્તહીઆ। અષ્̌આ। વીસ્પાણ્ગ્। સ્̌́ઇઇઅઓથઅના।વવંગહાઉસ્̌। ક્સરતૂમ્। મનંગહો। યા। ક્સષ્̌નાઉઉઈષ્̌આ। ગાઉસ્̌ચા। ઉરુઉઆનામ્।::
- "It is impossible to attribute a precise geographical location to the language of the Avesta... With the exception of an important study by P. Tedesco (1921 [...]), who advances the theory of an 'Avestan homeland' in northwestern Iran, Iranian scholars of the twentieth century have looked increasingly to eastern Iran for the origins of the Avestan language and today there is general agreement that the area in question was in eastern Iran—a fact that emerges clearly from every passage in the Avesta that sheds any light on its historical and geographical background."
- Nordhoff, Sebastian; Hammarström, Harald; Forkel, Robert; Haspelmath, Martin, eds. (2013). "Avestan". Glottolog 2.2. Leipzig: Max Planck Institute for Evolutionary Anthropology.
- Wells, John C. (1990), Longman pronunciation dictionary, Harlow, England: Longman, p. 53, ISBN 0-582-05383-8 entry "Avestan"
- Michael Witzel, THE HOME OF THE ARYANS, Harvard University, P.10
- Darmesteter, J. The Zend Avesta, Vol, Second Edition, London, 1895, pp. 253-8
- Boyce, A History of Zoroastrianism vol II & III, pp. 18 and 25. 1985 
- Mallory, J P (1997). Encyclopedia of Indo-European culture. page 653. London: Fitzroy Dearborn Publishers. ISBN 978-1-884964-98-5. entry "Yazd culture".
- Zoroastrians: Their Religious Beliefs and Practices by Mary Boyce (pg. 18)
- Hoffmann, Karl (1989), "Avestan language", Encyclopedia Iranica 3, London: Routledge & Kegan Paul, pp. 47–52.
- Gnoli, Gherardo (1989), "Avestan geography", Encyclopedia Iranica 3, London: Routledge & Kegan Paul, pp. 44–47.
- Encyclopaedia Iranica: EASTERN IRANIAN LANGUAGES. By Nicholas Sims-Williams
- Hoffmann, K. Encyclopaedia Iranica. AVESTAN LANGUAGE. III. The grammar of Avestan.: "The morphology of Avestan nouns, adjectives, pronouns, and verbs is, like that of the closely related Old Persian, inherited from Proto-Indo-European via Proto-Indo-Iranian (Proto-Aryan), and agrees largely with that of Vedic, the oldest known form of Indo-Aryan. The interpretation of the transmitted Avestan texts presents in many cases considerable difficulty for various reasons, both with respect to their contexts and their grammar. Accordingly, systematic comparison with Vedic is of much assistance in determining and explaining Avestan grammatical forms."
- Morgenstierne, G. Encyclopaedia Iranica: AFGHANISTAN vi. Paṧto "it seems that the Old Iranic ancestor dialect of Paṧtō must have been close to that of the Gathas."
- Beekes, Robert S. P. (1988), A Grammar of Gatha-Avestan, Leiden: Brill, ISBN 90-04-08332-4.
- Hoffmann, Karl; Forssman, Bernhard (1996), Avestische Laut- und Flexionslehre, Innsbrucker Beiträge zur Sprachwissenschaft 84, Institut fur Sprachwissenschaft der Universität Innsbruck, ISBN 3-85124-652-7.
- Kellens, Jean (1990), "Avestan syntax", Encyclopedia Iranica, 3/sup, London: Routledge & Kegan Paul
- Skjærvø, Prod Oktor (2006), Old Avestan, fas.harvard.edu.
- Skjærvø, Prod Oktor (2006), Introduction to Young Avestan, fas.harvard.edu.
- Avestan lessons, Grammar, Dictionaries at avesta.org
- Old Iranian (including Old and Young Avestan) at The University of Texas
- Old Avestan and Young Avestan at Harvard University
- Text samples and Avesta Corpus at TITUS.
- Boyce, Mary (1989), "Avestan people", Encyclopedia Iranica 3, London: Routledge & Kegan Paul, pp. 62–66.