This is the 13904th most frequent Polish word.
popełnienie
"Popełnienie" means "commission" or "the act of committing (e.g., a crime)."
Here, 'popełnienie' refers to the act of committing or making an error, used in a general context.
Popełnienie błędu jest częścią procesu nauki.
Committing a mistake is a part of the learning process.
In this sentence, 'popełnienie' is used to denote the act of carrying out an illegal activity, with legal consequences.
Za popełnienie przestępstwa grozi kara więzienia.
Committing a crime is punishable by imprisonment.
Here, 'popełnienie' is used somewhat ironically or contextually with an unusual formulation, implying performing the act of submitting something properly.