Open world PvP Zone

[Zojha]

You also had a choice in WoW, they had RP and PvE servers.

You could still get flagged PvP by accident if you buffed, healed or resurrected a player that had the tag on (AoE heals included). Then there were also Open World areas that automatically flagged you if you entered them (I think even flying over them by accident counted, but I'm not sure anymore) and then of course you regularly had PvP flagged people running into your mobs, onto your corpses (For those not in the know: You had to click on a corpse to loot it) and around you in order to try and get you PvP flagged via accidental misclick or AoE. Especially high level Tauren with their Kodos loved that strategy, since they had the most coverage.
Once flagged, you had to wait 5 minutes for the flag to vanish, which was the most annoying bit of it all. So even if you killed the dude, sticking around just made you prone to a gank while you're busy with another mob, you had to walk away and wait before continuing your farm.

It was a royal pain to avoid PvP on PvE servers at times. If you had a guild, it was usually easier to just kill the troublemakers and spawncamp them until they got bored and learned their lesson.