When police refer to the force that they belong to they mention the digits indivdually. Without knowing the show I will say that they are part of Squad 50, or Preceint 50 or something like that. ANd 50 is the number of Hawaii's statehood.
Growing up in the hood when the cops were coming we referred to them as "5 0" and it usually meant that it was time for us to go.
the task force 5 0 is made up of 5 officers
it means the police/ officer.
It,s fifty as in the fiftieth state.
Hawaii five o
In the old series the 5-O was also a play on Hawaii being the 50th state