The word "MarJohn" is a rarely used proper noun that features the use of two common vowel sounds in English - the "ah" and "oh" sounds. In IPA phonetic transcription, "MarJohn" can be spelled as /mɑrˈdʒɑn/, breaking down into the sounds "m-ah-r" and "dʒ-oh-n". This word is often seen as a name or title, and is not commonly used in everyday conversation. It is important to recognize and understand the spelling of all words, whether they are commonly used or not.