The spelling of the word "Casuistieal" can be broken down using IPA phonetic transcription. The first syllable is /kæz/ which is followed by /ju/ in the second. The third syllable is spelled with /sti/ while the fourth and final syllable is /əl/. The /z/ sound in the first syllable is spelled with a "z" while the /j/ sound in the second syllable is spelled with a "u". The "ie" in the third syllable makes the /i/ sound and the "eal" in the final syllable makes a schwa sound.