This is the 6671st most frequent Polish word.
dunajcem
"Dunajcem" is the instrumental case of "Dunajec," a river in Poland. It means "with/by the Dunajec."
Here, 'Dunajcem' is used in the instrumental case of 'Dunajec,' suggesting means of travel or the instrument of action.
Podróżowaliśmy Dunajcem, aby zobaczyć piękne góry.
We traveled by Dunajec to see the beautiful mountains.
In this instance, 'Dunajcu' is in the locative case, indicating a location or position.
Wędkarze często łowią ryby w Dunajcu.
Fishermen often catch fish in the Dunajec.
The usage here, 'Dunajcem,' reflects the instrumental case to imply a spatial relationship.