Where does “prostředník” come from?

prostředník (Czech) comes from Czech -ník, from Old Czech -ník, from Proto-Slavic -ьnikъ, from Proto-Slavic -ikъ — *nožь → *nožikъ; *větrъ → *větrikъ; *listъ →...

prostředník (Czech): middle finger

Definitions

middle finger

Ancestry of “prostředník”, step by step

Step	Language	Word	Meaning
1	Czech	-ník	Nominal suffix
2	Old Czech	-ník	nominal suffix
3	Proto-Slavic	-ьnikъ	From base concept nouns, forms agent nouns who...
4	Proto-Slavic	-ikъ	nožь → nožikъ; větrъ → větrikъ; *listъ →...

Every word from Proto-Slavic -ikъ →Every word from Czech -ník →Every word from Proto-Slavic -ьnikъ →