OP was clarifying the meaning of pirate in the present context, not the origin of the term or how it is used in some other contexts. The meaning you're suggesting is very explicitly not the idea behind the Icelandic Pirate Party.

At one point, they publicly rejected any affiliation with The Pirate Bay and said that they did not condone copyright violations.

They did however use the opportunity to encourage people to learn about openly licensed content, mentioning Paulo Coelho as an example, and suggesting that people consume free content no less than they do paid content. However advisable or realistic that actually is, it's not supporting illegal downloads.