アヴェスター語において、''ātar''は熱源や光源の属性であり、その主格単数形は''ātarš''であり、ペルシア語の''ātaš''(火)の語源である。
かつては、アヴェスター語の āθrauuan / aθaurun(ヴェーダ語 atharvan)という一種の祭司と語源的に関連すると考えられていたが、現在ではその可能性は低いとされている(Boyce, 2002:16)。以前は不明とされていた ātar の最終的な語源(Boyce, 2002:1)は、現在ではインド・ヨーロッパ祖語の*h<sub>x</sub>eh<sub>x</sub>tr-「火」に由来すると考えられている。これにより、ラテン語 ater(黒)や、アルバニア語 vatër(定形:vatra)「炉」「暖炉」と同根語となる。アルバニア語のこの語はルーマニア語 vatră「炉」「暖炉」へ借用され、さらにそこからセルボ・クロアチア語 vatra「火」やウクライナ語 vatra「たき火」へと広まった<ref>jstor:40997529, The Prehistory of the Albanian Vowel System: A Preliminary Exploration, Studies in Slavic and General Linguistics, volume32:Evidence and Counter-Evidence: Essays in honour of Frederik Kortlandt. v 1: Balto-Slavic and Indo-European Linguistics, p591–608, Vermeer Willem, 2008, "Romanian also famously borrowed ''vatër'' 'hearth' with patently Tosk ''va-'' and proceeded to spread it to wherever Vlachs expanded subsequently."</ref><ref>https://books.google.com/books?id=tzU3RIV2BWIC&q=atars&pg=PA202, Encyclopedia of Indo-European Culture - James Mallory - Google Boeken, 2012-08-27, isbn:9781884964985, Mallory J. P., Adams Douglas Q., 1997, Taylor & Francis</ref>。
In the [[Avestan language]], 後期ゾロアスター教では、''ātar'' is an attribute of sources of heat and light, of which the nominative singular form is ''ātarš'', source of [[Persian language|Persian]] ''ātaš'' (fire). It was once thought to be etymologically related to the [[Avestan]] ''āθrauuan'' / ''aθaurun'' ([[Vedic Sanskrit|Vedic]] ''[[atharvan]]''), a type of priest, but that is now considered unlikely (Boyce, 2002:16). The ultimate etymology of ''ātar'', previously unknown (Boyce, 2002:1), is now believed to be from the [[Proto-Indo-European language|Indo-European]] *h<sub>x</sub>eh<sub>x</sub>tr- 'fire'. This would make it a cognate to [[Latin]] ''[[wikt:ater#Latin|ater]]'' (black) and to [[Albanian language|Albanian]] ''[[vatër]]'' (definite form: ''vatra'') "hearth", "fireplace", which was loaned to [[Romanian language|Romanian]] ''vatră'' "hearth", "fireplace", and thereafter spread to [[Serbo-Croatian language|Serbo-Croat]] ''vatra'' "fire" and [[Ukrainian language|Ukrainian]] ''vatra'' "bonfire".<ref>{{Cite journal |jstor = 40997529|title = The Prehistory of the Albanian Vowel System: A Preliminary Exploration|journal = Studies in Slavic and General Linguistics|volume = 32:Evidence and Counter-Evidence: Essays in honour of Frederik Kortlandt. v 1: Balto-Slavic and Indo-European Linguistics|pages = 591–608|last1 = Vermeer|first1 = Willem|year = 2008|quote="Romanian also famously borrowed ''vatër'' 'hearth' with patently Tosk ''va-'' and proceeded to spread it to wherever Vlachs expanded subsequently."}}</ref><ref>{{cite book|url=https://books.google.com/books?id=tzU3RIV2BWIC&q=atars&pg=PA202 |title=Encyclopedia of Indo-European Culture - James Mallory - Google Boeken |access-date=2012-08-27|isbn=9781884964985 |last1=Mallory |first1=J. P. |last2=Adams |first2=Douglas Q. |year=1997 |publisher=Taylor & Francis }}</ref> In later Zoroastrianism, ''ātar'' ([[Persian language|Middle Persian]]: 𐭠𐭲𐭥𐭥𐭩 (中世ペルシア語:𐭠𐭲𐭥𐭥𐭩 ''ādar'' or または ''ādur'') is iconographically conflated with fire itself, which in Middle Persian is )は、図像学的に火そのものと同一視されており、火は中世ペルシア語では 𐭠𐭲𐭧𐭱 ''ātaxsh'', one of the primary objects of Zoroastrian symbolism. と呼ばれ、ゾロアスター教の主要な象徴の一つだった。
== 解説 ==