The spelling of the word "most whopper" can be confusing. It sounds like /moʊst ˈwɒpər/ and is used to describe something that is extremely large or impressive. The word "most" is spelled as it is pronounced but the word "whopper" is spelled differently than it sounds. The letter "h" is silent and the two "p"s are used to indicate the length of the vowel sound in the second syllable. So, next time you use the word, remember to spell it as "whopper" and not "wopper".