The spelling of the word "OOSHIN" can be a bit confusing for those unfamiliar with its pronunciation. Using the International Phonetic Alphabet (IPA) can help clarify the spelling. The first sound is a long "oo" sound, represented by the IPA symbol /u/. The second sound is a short "sh" sound, represented by /ʃ/. The final sound is a nasal "n" sound, represented by /n/. Therefore, the correct spelling of the word "OOSHIN" using IPA is /uːʃɪn/.