This is the 12282nd most frequent Portuguese word.
saco
Bag; sack.
Here, 'saco' refers to a container or bag used to carry or store items.
Eu comprei um saco de batatas no mercado hoje.
I bought a bag of potatoes at the market today.
This usage conveys 'saco' metaphorically as a collection or multitude of challenges or issues.
Estou cheio desse saco de problemas que surgem todos os dias.
I'm fed up with this sack of problems that arise every day.
In this sentence, 'saco' is used colloquially to express annoyance or frustration, equivalent to saying 'what a drag!'