The spelling of "more spun" is based on the phonetic sounds of the English language. "More" is pronounced as /mɔːr/, with the "or" sound represented by the letter "o" and the "r" sound by the letter "r". "Spun" is pronounced as /spʌn/, with the "u" sound represented by the letters "u" and "n" for the nasal sound. The combination of the two words results in the phrase /mɔːr spʌn/. The spelling of words in English is crucial for clear communication and understanding.