Zahhak

Zahhāk or Zahāk (pronounced [zæhɒːk]) (in Persian: ضحّاک‎‎/ذهّاک) or Bivar Asp (Persian: بیوَر اَسپ‎‎ meaning "he who owns ten thousands of horses") is an evil figure in Iranian mythology, evident in ancient Iranian folklore as Aži Dahāka (Azh dahak), the name by which he also appears in the texts of the Avesta. In Middle Persian he is called Dahāg or Bēvar-Asp, the latter meaning "[he who has] 10,000 horses". In Zoroastrianism, Zahak (going under the name Aži Dahāka) is considered the son of Angra Mainyu, the foe of Ahura Mazda.

Aži (nominative ažiš) is the Avestan word for "serpent" or "dragon." It is cognate to the Vedic Sanskrit word ahi, "snake," and without a sinister implication. Azi and Ahi are distantly related to Greek , Latin , Russian and Old Church Slavonic (grass-snake), all meaning "snake".

The original meaning of dahāka is uncertain. Among the meanings suggested are "stinging" (source uncertain), "burning" (cf. Sanskrit dahana), "man" or "manlike" (cf. Khotanese daha), "huge" or "foreign" (cf. the Dahae people and the Vedic dasas). In Persian mythology, Dahāka is treated as a proper noun, and is the source of the Ḍaḥḥāk (Zahhāk) of the Shāhnāme.

The Avestan term Aži Dahāka and the Middle Persian azdahāg are the source of the Middle Persian Manichaean demon of greed Az, Old Armenian mythological figure , modern Persian aždehâ / aždahâ and Tajik Persian azhdahâ and Urdu Azhdahā (اژدها) as well as the Kurdish ejdîha (ئەژدیها) which usually mean "dragon".

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