The correct spelling of the word "out sun" is actually "outson", with the phonetic transcription /aʊtˈsʌn/. The confusion arises from how the two words "out" and "sun" are pronounced together, with the vowel sounds blending into one another. This is known as a diphthong, where the sound glides between two vowels. The "ou" in "out" sounds like the "ow" in "how", while the "u" in "sun" sounds like the "uh" in "up". Together they form the sound /aʊ/, as in "house" or "cow".