That Zam—Zahhak-e-Maar-Doosh (Aži Dahāka in Avestan, Azhdshak in Middle Persian)—is the king of dragons, who slew Jamshid.
ðæt zˈæm—zˈɑːhækˈiːmˈɑːɹdˈuːʃ ˈæʒi dæhˈɑːkə ɪn ˌævɪstˈɑːn, ˈæʒdʃæk ɪn mˈɪdəl pˈɜːʒən—ɪz ðə kˈɪŋ ʌv dɹˈæɡənz, hˌuː slˈuː dʒˈæmʃɪd.