The correct spelling of the word "Carphecillin" can be explained through its IPA phonetic transcription. The first syllable, "carp", is pronounced with a /k/ sound, followed by a diphthong /æɪ/ in the second syllable "phe," which rhymes with "way." The third syllable "cil" is pronounced with a soft /s/ sound and a short /ɪ/ vowel sound. The final syllable "lin" is pronounced with a soft /l/ sound and a short /ɪ/ vowel sound. Together, the word forms a unique combination of sounds that make it distinct and memorable.