The spelling of the word "ICASA" can be explained by its International Phonetic Alphabet (IPA) transcription: /aɪˈkɑːsə/. The first sound, /aɪ/, represents the diphthong "ai" in "ice," while the following syllable, /kɑː/, denotes the vowel "a" in "car." Lastly, the final syllable, /sə/, corresponds to the schwa sound "uh" in "sofa." Together, the IPA transcription explains the correct spelling of "ICASA," which is commonly used as an acronym for the Independent Communications Authority of South Africa.