The spelling of the word "sisson" may seem unusual, but it follows the rules of English phonetics. The IPA phonetic transcription of "sisson" is /ˈsɪsən/, which indicates that the first syllable is pronounced with a short "i" sound, and the second syllable has a soft "s" and an unstressed "uh" sound. The double "s" in "sisson" indicates a voiceless "s" sound, rather than a "z" sound. Overall, the spelling accurately reflects the pronunciation of the word.