The spelling of the word "ballu" is relatively straightforward when using the International Phonetic Alphabet (IPA). The word is pronounced /bælu/, with the first syllable rhyme with "cat" and the second syllable rhyme with "dew". The "b" indicates the initial consonant sound, followed by the vowel sounds "a" and "u" respectively. This phonetic transcription clarifies the spelling of the word "ballu" and ensures accurate pronunciation.