adj. Pirate drunk is the condition whereas you are so drunk, that you see double. To compensate, you cover one eye (like a pirate's eye patch). Typically, you are so drunk that you do not have a problem talking to someone seated next to you with one hand over your eye.
Lisa, "Tom called me from the bar last night, and I couldn't understand a word he said. He was totally pirate drunk."
MD, "He was at the Cubs game that afternoon, so it's not a big surprise."