noun. As peesome threesomes are to gruesome twosomes, so is a triple-ganger to a doppelganger.
Real citation: "UPDATE: Several readers write in to clarify. One says, "That picture is not 'the' Rod Stewart doppelganger I see regularly on the F Train and at the NYSC in the Crowne Plaza and going to work somewhere in or near the Times building. So maybe there's a triple-ganger somewhere." Developing!"
("Rod Stewart Doppelganger Update: Have You Seen This Man?" Dec. 2, 2004, Gawker, http://www.gawker.com/news/culture//rod-stewart-doppelganger-update-have-you-seen-this-man-026760.php)
Made-up citation: "I've been coping quite well with my evil twin, but now that my dastardly triple-ganger has emerged, life sucks."