The word "acapnial" is spelled with the letters A-C-A-P-N-I-A-L. Its phonetic transcription in IPA is /ˌækəpˈnaɪəl/. The first syllable, "ac," is pronounced like "ack," followed by the short "a" sound in "uh." The second syllable, "ap," rhymes with "cap" and is followed by the long "i" sound in "eye." The third syllable, "ni," is pronounced like "nye," and the final syllable, "al," is pronounced with a long "a" sound, like "ale."