Where does “inactinic” come from?

inactinic (English) comes from English in, from Middle English in, from Old English in, from Proto-West Germanic *in.

inactinic (English): That does not produce photochemical reactions

Definitions

  1. That does not produce photochemical reactions

Ancestry of “inactinic”, step by step

inactinic traces back through two separate lines of ancestry.

via English in

StepLanguageWordMeaning
1EnglishinUsed to indicate location, inclusion, or position...
2Middle EnglishinAny kind of accomodation; particularly; A home or...
3Old Englishinin; Alternative form of inn
4Proto-West Germanic*in

via English actinic

StepLanguageWordMeaning
1EnglishactinicOf or relating to actinism; Composed of actin;...
2Ancient Greekἀκτίςray, beam; brightness, splendor; spoke
Every word from Proto-West Germanic *inEvery word from Old English inEvery word from Middle English in