Where does “rimeless” come from?

rimeless (English) comes from English rime, from Middle English rime, from Old English rīm, from Proto-Germanic rīmą, from Proto-Indo-European h₂rey-, from Proto-Indo-European h₂er- — to fit, to fix, to put together.

Ancestry of “rimeless”, step by step

rimeless traces back through two separate lines of ancestry.

via English rime

StepLanguageWordMeaning
1EnglishrimeIce formed by the rapid freezing of cold water...
2Middle Englishrimenumber
3Old Englishrīmcounting; number, counting, reckoning;...
4Proto-Germanicrīmącalculation, number
5Proto-Indo-Europeanh₂rey-to count, count out; to arrange
6Proto-Indo-Europeanh₂er-to fit, to fix, to put together

via English less

StepLanguageWordMeaning
1EnglishlessTo a smaller extent or degree; comparative form...
2Middle Englishlesfalse; lying; deceptive; falsehood; a lie
3Old Englishlēasfalse, lax; false, void, loose; devoid of, loose...
4Proto-Germanic*laus
Every word from Proto-Indo-European h₂er-
rimeless — Etymology, Origin & Word History | Etymology Explorer