The spelling of the word "apilary" can be explained through its IPA phonetic transcription. The first syllable "a-" is pronounced as the schwa sound /ə/, followed by the sound /p/ for the letter "p". The second syllable is pronounced with a long vowel sound as /aɪ/, represented by the letters "i" and "y". The final syllable "-lary" is pronounced with the consonant sound /l/ followed by the vowel sound /ɛ/ for the letter "e". Altogether, the word is pronounced as /əp-aɪ-lɛr-i/.