The spelling of the word "more ardorless" can be explained using IPA phonetic transcription. The word "more" is pronounced as /mɔːr/ and means "in a greater quantity, number, or degree". "Ardorless" is pronounced as /ˈɑː.dər.ləs/ and means "lacking enthusiasm or passion". When combined, "more ardorless" means having even less enthusiasm or passion than before. The spelling is straightforward and accurate, reflecting the meaning of the words as they are combined.
There seems to be a misunderstanding or mistake in the word "more ardorless". "Ardorless" itself is not a recognized word in English, and the phrase "more ardorless" does not have a defined etymology.
However, the word "ardor" does have its own etymology. It comes from the Latin word "ardere", meaning "to burn" or "to be on fire". "Ardor" was adopted into Middle English from Old French, where it derived from the Latin form. It originally referred to intense heat or burning, but over time, its meaning expanded to include passion, enthusiasm, or fervor.