This is the 14145th most frequent Polish word.
pożarnictwem
The Polish word "pożarnictwem" translates to "firefighting" in English.
This demonstrates the noun 'pożarnictwem' in the instrumental case, used to indicate the field of firefighting as a hobby.
Interesuję się pożarnictwem od dziecka.
I have been interested in firefighting since childhood.
The noun 'pożarnictwem' is in the instrumental case here, indicating the professional field in which someone was involved.
Pożarnictwem zajmował się mój dziadek.
My grandfather worked in firefighting.
This usage of 'pożarnictwem' in instrumental case describes an aspirational relationship to the professional field of firefighting.