This is the 17372nd most frequent Polish word.
zapomnieć
"Zapomnieć" means "to forget."
The verb 'zapomnieć' is used here to express forgetting to do a specific action.
Zapomniałem zamknąć drzwi.
I forgot to close the door.
In this sentence, 'zapomnieć' indicates the difficulty or impossibility of erasing a memory of something.
Nie mogę zapomnieć tej piosenki.
I can't forget this song.
Here, 'zapomnieć' reflects the intention or effort to remove a memory or impression of a particular occurrence.