Where does “taitekerroin” come from?
taitekerroin (Finnish) comes from Finnish taite, from English thursday, from Middle English Thursday, from Old English þursdæġ, from Proto-Germanic *Þunras dag, from Latin dies iovis, from Latin diēs, from Proto-Italic djēm — to be bright; sky, heaven.
taitekerroin (Finnish): refractive index
Ancestry of “taitekerroin”, step by step