This is the 3952nd most frequent Polish word.
sącz
The Polish word "sącz" means "drain" or "seep."
Here, 'sącz' is used as a verb meaning 'sip' or 'drink slowly'.
Sącz kawę powoli, aby się nie oprzeć.
Sip the coffee slowly to savor it.
In this case, 'Sącz' is part of a proper noun, the name of a city.
Nowy Sącz to miasto w południowej Polsce.
Nowy Sącz is a city in southern Poland.
In this context, 'sącząc' is a gerund form of the verb, meaning 'sipping'.