The spelling of the word "XITBILI" can be explained using the International Phonetic Alphabet (IPA) transcription. The first sound is /ks/ represented by the letter X, followed by the vowel sound /ɪ/ represented by I. The next consonant sound is /t/ represented by T, followed by the voiced bilabial fricative sound /β/ represented by B. The final two sounds are /i/ represented by I and /l/ represented by L. Therefore, the correct spelling of this word is "XITBILI."