Where does “neplausibilní” come from?

neplausibilní (Czech) comes from Czech ně-, from Czech ne, from Old Czech ne, from Proto-Slavic ne, from Proto-Balto-Slavic nē, from Proto-Indo-European né — not; no.

Ancestry of “neplausibilní”, step by step

StepLanguageWordMeaning
1Czechně-some
2Czechneno!; not
3Old CzechneNegation particle; no, not
4Proto-Slavicnenot
5Proto-Balto-Slavicnēnot
6Proto-Indo-Europeannénot; no
Every word from Proto-Indo-European né →Every word from Proto-Balto-Slavic nē →Every word from Czech ně- →