Where does “Zimoch” come from?

Zimoch (Polish) comes from Polish -och, from Polish -ch, from Old Polish -ch, from Proto-Slavic -xъ.

Ancestry of “Zimoch”, step by step

Step	Language	Word	Meaning
1	Polish	-och	Used with a verb to form a masculine noun that is...
2	Polish	-ch	Attached to truncated stems of common nouns to...
3	Old Polish	-ch	Attached to truncated stems of masculine given...
4	Proto-Slavic	-xъ	—