Verethragna (vərəθraγna) is an Avestan language neuter noun literally meaning "smiting of resistance" (Gnoli, 1989:510; Boyce 1975:63). Representing this concept is the divinity Verethragna, who is the hypostasis of "victory", and "as a giver of victory Verethragna plainly enjoyed the greatest popularity of old" (Boyce, 1975:63).
The neuter noun verethragna is related to Avestan verethra, 'obstacle' and verethragnan, 'victorious'. (Gnoli, 1989:510) In Zoroastrian Middle Persian, Verethragna became Warahran, from which Vahram, Vehram, Bahram, Behram and other variants derive.
Verethragna descends from an Indo-Iranian god known as *vrtra-g'han- (virtually PIE *wltro-gwhen-) "slayer of the blocker".
The name and, to some extent, the deity has correspondences in Armenian Vahagn and Vram, Sogdian Wshn, Parthian Wryhrm, and Kushan Orlagno. While the figure of Verethragna is highly complex, parallels have also been drawn between it and (variously) Vedic Indra, Puranic Vishnu, Manichean Adamas, Chaldean/Babylonian Nergal, Egyptian Horus, Hellenic Ares and Heracles.
Read more about Verethragna: In Avestan Scholarship