Correct spelling for the English word "arsenauro" is [ˌɑːsənˈɔːɹə͡ʊ], [ˌɑːsənˈɔːɹəʊ], [ˌɑː_s_ə_n_ˈɔː_ɹ_əʊ] (IPA phonetic alphabet).
Trade name of a preparation of the bromides of arsenic and gold employed in the treatment of syphilis.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.