The word "dimmitt" is spelled with two "m's" and two "t's". The IPA phonetic transcription for this word is /ˈdɪmɪt/. The first sound is /d/ as in "dog", followed by /ɪ/ as in "sit". The second syllable is /m/ as in "mother" and /ɪ/ again. The final syllable is /t/ as in "top" and again, /t/. This word is not commonly used and may refer to a person's last name or the name of a place.
There doesn't seem to be a widely recognized or documented etymology for the word "dimmitt". It is possible that "dimmitt" is a surname or a proper noun, rather than a common word with a specific origin or history. If you have any additional context or information about the word, it might be helpful in providing a more accurate answer.