The correct spelling of the phrase "most travelling" is with a double L, as in "Travelling" instead of "Traveling". This is because it follows British English spelling rules, which generally use double L for words ending in -l after an unstressed syllable. The IPA phonetic transcription for most travelling would be /məʊst ˈtrævəlɪŋ/. So, if you're writing in British English, remember to use double L when spelling words like "traveller", "cancelled", and "enrolled".
The phrase "most travelling" does not have a specific etymology since it is a combination of the adjective "most" and the present participle of the verb "travel" ("travelling"). However, we can explore the etymology of the word "travel" itself.
The word "travel" comes from the Middle English word "travaylen", which originally meant "to labor, toil" or "to journey". It was derived from the Old French word "travailler" meaning "to work, labor".
The Old French word "travailler" can be traced back to the Medieval Latin word "tripaliare" or "trepaliare", which meant "to torture or torment" and was derived from the Latin word "tripalium" referring to an instrument of torture.