Note 043
Medinat al Salem, Dar al Salem. Urbs pacis, or, as it is more neatly compounded by the Byzantine writers, Ancient Greek (Irenopolis.) There is some dispute concerning the etymology of Bagdad, but the first syllable is allowed to signify a garden in the Persian tongue; the garden of Dad, a Christian hermit, whose cell had been the only habitation on the spot.
The History Of The Decline And Fall Of The Roman Empire Fall In The EastChapter 52