The word "arsinous" is a rare and obscure word that refers to something that contains arsenic. The spelling of this word can be explained using IPA phonetic transcription: /ɑːsɪnəs/. The first syllable is pronounced with a long "a" sound, while the second syllable has a short "i" sound. The final syllable is pronounced with a soft "s" sound. While not commonly used in everyday language, the correct spelling and pronunciation of "arsinous" is important when discussing toxic or hazardous materials.