Otho, Marcus Salvius Syllabification: (O·tho, Marcus Salvius)Pronunciation: /ˈōTHō/Definition of Otho, Marcus Salvius ( ad 32-69), Roman emperor from January until April of 69. Proclaimed emperor after the death of Galba, he was defeated by Vitellius and his German legions and committed suicide. Otho, Marcus Salvius in other Oxford dictionaries Definition of Otho, Marcus Salvius in the British & World English dictionary