Where does “nappulasarja” come from?

nappulasarja (Finnish) comes from Finnish sarja, from Proto-Finnic sarja, from Proto-Finno-Permic śarja — lath, batten, bar.

Ancestry of “nappulasarja”, step by step

nappulasarja traces back through two separate lines of ancestry.

via Finnish sarja

StepLanguageWordMeaning
1Finnishsarjaseries; chain, sequence, succession, train; set
2Proto-Finnicsarjarow of laths or battens; a board made of laths
3Proto-Finno-Permicśarjalath, batten, bar

via Finnish nappula

StepLanguageWordMeaning
1Finnishnappulapush button; stone, man; kid, child
2Finnishnäppithe tips of the thumb and another finger or...
3Proto-Finnicnäppifingertip, finger
Every word from Proto-Finno-Permic śarja