The spelling of the phrase "most bigname" is straightforward when considering the individual words. "Most" is spelled as it sounds: /moʊst/. "Bigname" is a compound word made up of "big" and "name." The pronunciation and spelling of "big" is /bɪɡ/, while "name" is pronounced and spelled /neɪm/. Therefore, the correct spelling of "most bigname" reflects the phonetic accuracy of each word: /moʊst bɪɡneɪm/. This phrase is often used to describe a highly recognizable or famous individual.