This is the 14271st most frequent Polish word.
prostownik
A "prostownik" is a rectifier or a device that converts alternating current (AC) to direct current (DC).
In this context, "prostownik" refers to a device used to convert alternating current (AC) to direct current (DC), often used for charging car batteries.
Kupiłem nowy prostownik do ładowania akumulatorów.
I bought a new rectifier for charging batteries.
Here, "prostownik" is the electronic component within a device transforming electrical currents for its operation.
Prostownik w moim telewizorze przestał działać, co wymagało jego naprawy.
The rectifier in my television stopped working, which required its repair.
This sentence demonstrates a figurative and less common usage of "prostownik" to mean a device or tool that 'straightens' or corrects something, in this case, posture.