Iranica:

SIMORḠ (Persian), Sēnmurw (Pahlavi), Sīna-Mrū (Pāzand), a fabulous, mythical bird. The name derives from Avestan mərəγō saēnō ‘the bird Saēna’, originally a raptor, either eagle or falcon, as can be deduced from the etymologically identical Sanskrit śyená. Saēna is also attested as a personal name which is derived from the bird name.

In the Avestan Yašt 14.41 Vərəθraγna, the deity of victory, wraps xᵛarnah, fortune, round the house of the worshipper, for wealth in cattle, like the great bird Saēna, and as the watery clouds cover the great mountains, which means that Saēna will bring rain. In Yašt 12.17 Saēna’s tree stands in the middle of the sea Vourukaša, it has good and potent medicine, is called all-healing, and the seeds of all plants are deposited on it. This scanty information is supplemented by the Pahlavi texts. In the Mēnōg ī Xrad (ed. Anklesaria, 61.37-41) the Sēnmurw’s nest is on the “tree without evil and of many seeds.” When the bird rises, a thousand shoots grow from the tree, and when he (or she) alights, he breaks a thousand shoots and lets the seeds drop from them. The bird Cīnāmrōš (Camrōš) collects the seeds and disperses them where Tištar (Sirius) will seize the water with the seeds and rain them down on the earth. While here the bird breaks the branches with his weight, in Bundahišn 16.4 (tr. Anklesaria) he makes the tree wither, which seems to connect him with the scorching sun. An abbreviated form of this description is found in Zādspram 3.39; a gloss on the Pahlavi translation of Yašt 14.41 confuses the tree of many seeds with the tree of the White Hōm. Two birds are involved in the scattering of the seeds also in the New Persian Rivāyat of Dārāb Hormazyār (tr. Dhabhar, p. 99), here called Amrōš and Camrōš, Amrōš taking the place of Sēnmurw; these names derive from Avestan amru and camru, personal names taken from bird names...

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