The spelling of the word Endosprin can be explained using IPA phonetic transcription. The first two syllables "en-do" correspond to the phonemes /ˈɛndəʊ/. The final syllable "sprin" corresponds to /sprɪn/. Therefore, the complete spelling of the word in IPA phonetic transcription is /ˈɛndəʊsprɪn/. This word is not commonly used in everyday language and is more likely to be used in medical or scientific contexts, referring to a type of medication or protein.