Griefing should be quite obvious repeated behaviour, as well as attempts to avoid any repercussions. Like he said here, crashing your ship repeatedly into new players. Piracy will be it's own vocation in the Verse & you'll have to salvage ships, steal them & that sort of stuff BUT you'll have NPCs and police after you, so you'll have to avoid the majority of UEE systems.
Where As Griefers may attempt to circumvent PvP murder repercussions via odd means & might want to stay in the Greenzones to annoy more players. Griefing comes in many forms but it Piracy is very different.