馬頭観音 (hiragana ばとうかんのん, romaji Batō Kannon, historical hiragana ばとうくわんおん)
馬頭 (batō, “horse head”, calque of Sanskrit हयग्रीव (hayagrīva)) + 観音 (Kannon, “Guanyin”). The on reading for 音 changes to non as an instance of renjō (連声).