The correct spelling of the word "Biotidin" follows the International Phonetic Alphabet (IPA) pronunciation rules. The word is pronounced as /baɪˈɒtɪdɪn/ - with the stressed syllable being on the second to last vowel sound. The phonetic transcription implies that the first syllable is pronounced with a long "i" sound, followed by an "o" that makes a short "o" sound. The word ends with a stressed syllable that is pronounced with a short "i" sound and ends in the letter "n".