This is the 12321st most frequent Polish word.
mocą
"By the power of" or "under the authority of."
instrumental case denoting 'by the authority of'
Nowa ustawa została przyjęta mocą parlamentu.
The new law was passed by the authority of the parliament.
instrumental case denoting 'through the power/force of'
Mocą swojej determinacji udało mu się pokonać trudności.
Through his determination, he managed to overcome difficulties.
instrumental case denoting 'by means of'