Check a recent dictionary. Take it up with Princeton if you don't like the definition:

* (pirate) copy illegally; of published material

* (pirate) someone who robs at sea or plunders the land from the sea without having a commission from any sovereign nation

* (pirate) commandeer: take arbitrarily or by force; "The Cubans commandeered the plane and flew it to Miami"

The parents point was that it is not confused with 'stealing' though. Whilst, as you and I both noted it in fact means stealing (well robbing).

Copyright infringement is just that, or 'unlawful copying' if you're afraid of longer words.

Except it also means, as per pretty much every dictionary, to copy unlawfully. The same cannot be said of theft/stealing.

So if a headline refers to, let's say, 'Somali pirates' you disavow any confusion in the scope of activity in which the subjects are engaged?

In which case you rely on the context (you know, like you have to do with every other ambiguity in English ^^)

Considering how often Somalian criminals have been hijacking ships, and how this has been covered on pretty much every media form, I don't think there will be any confusion on this matter anytime soon.

Also, the verb form (Someone is pirating something) is in my experience almost exclusively used for copyright infringement. I've never heard of pirates pirating a shipment, but I've heard plenty of pirates pirating music.