A farm on PIMD is someone you can/do battle over and over. Farming in PIMD is hitting someone 5x or more in a 24 hour period.
The real meaning of farm is pimd is when you wake up in the middle of night cuz of a nightmare and then you start remembering that earlier today u ignored to help that old lady tryna cross the street and you start praying to the gods of skyrim to help you with your nightmares cuz u gotta sleep for work in 3 hours but skyrim gods also have nightmares so shame on you. Lol wut?