The spelling of the phrase "has notion" can be explained using the International Phonetic Alphabet (IPA). "Has" is pronounced /hæz/ and "notion" is pronounced /ˈnoʊʃən/. The "s" in "has" is pronounced as a voiced "z" sound because the accompanying vowel is voiced. The "t" in "notion" is replaced with a "sh" sound (represented by the letter combination "tion") due to the influence of the following "i" and "o" vowels. Therefore, the phrase is spelled as "has notion" but pronounced as /hæz ˈnoʊʃən/.