Bydgoszcz, originally Bydgoszcza (feminine), is a pronoun name the second part of which - 'goszcz' comes from 'gost-jь' possibly or 'gost-ja' an old Slavic root which refers to an urban or suburban trading settlement.
The name 'Byd-gost' contains archaic elements of the Proto-Slavonic root 'byd' which existed as a variant of the verb 'to raise' (Ancient Russian 'vъzbydati' = stimulating, Proto-Slavonic 'bъděti' / 'bъd 'ǫ' = no sleep, to watch),[REF] and the common Slavic root 'Goszcz' (fireplace).