The spelling of the word "for sit" might be confusing to some because it's not a phrase commonly used in English. However, if we break it down in terms of phonetics, it becomes clearer. The first word, "for," is spelled with the phonemes /f/ and /ɔr/ (as in "four"). The second word, "sit," is spelled with the phonemes /s/ and /ɪt/. Therefore, the correct spelling of "for sit" would be "for sit" because it adheres to the pronunciation of these phonemes.
The phrase "for sit" does not have a distinct etymology as it is not a commonly used or recognized phrase. It appears to be a combination of the preposition "for" and the verb "sit". "For" comes from Old English "for" which means "on account of" or "as a benefit to". "Sit" comes from Old English "sittan" which means "to sit" or "to remain in a seated position". However, it is important to note that "for sit" as a phrase may not have a specific etymology, and its meaning would depend on the context in which it is used.