The spelling of the word "WARNISTURA" can be explained using the International Phonetic Alphabet (IPA). In IPA, "W" is /w/, "A" is /ɑ/, "R" is /r/, "N" is /n/, "I" is /i/, "S" is /s/, "T" is /t/, "U" is /u/, and "RA" is /rɑ/. Therefore, the correct IPA spelling of this word is /wɑrnɪsturɑ/. This complex word may be a challenge for some spellers, but mastering the IPA transcriptions can make it easier to understand and spell unfamiliar words.