The word "most bowing" is spelled with a long "o" sound in both the first and second syllables. The IPA phonetic transcription for this word is /moʊst ˈboʊɪŋ/. The "o" in "most" is pronounced as a diphthong, with the lips rounded, while the "o" in "bowing" is pronounced with an open-mouthed, back-of-throat sound. The "w" in "bowing" is not pronounced, and the stress falls on the second syllable. "Most bowing" means the act of bending forward in respect or submission.
There is no recognized word or phrase "most bowing" in the English language. It is possible that there may be a typo or misspelling in your question. If you meant to ask about the etymology of another word or phrase, please clarify.