Where does “niemrawiasty” come from?

niemrawiasty (Polish) comes from Polish niemrawy, from Czech nemravný, 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 “niemrawiasty”, step by step

Step	Language	Word	Meaning
1	Polish	niemrawy	sluggish, slow, lethargic
2	Czech	nemravný	dissolute, immoral, indecent
3	Czech	ne	no!; not
4	Old Czech	ne	Negation particle; no, not
5	Proto-Slavic	ne	not
6	Proto-Balto-Slavic	nē	not
7	Proto-Indo-European	né	not; no

Every word from Proto-Indo-European né →Every word from Proto-Balto-Slavic nē →Every word from Proto-Slavic ne →