The spelling of the word "ISTONR" is inconsistent with English phonetics. Using IPA phonetic transcription, the word may be pronounced as "ɪstɑnər." However, this still does not correspond to standard English pronunciation as the "r" sound is typically pronounced at the end of words. It is possible that the word "ISTONR" is a misspelling or a made-up word with its own unique pronunciation. In any case, it is important to use proper spelling and pronunciation to effectively communicate in English.