Editor's Note: This entry contains minor spoilers for Star Wars Episode VII: The Force Awakens; read at your own caution.
TR-8R the Stormtrooper, also known as Tray Tor and TR8-T0R, refers to a character from the sci-fi space opera film Star Wars Episode VII: The Force Awakens who confronts and duels former-Stormtrooper-turned-Resistance-fighter Finn, calling him a "traitor." The trooper is notable for his use of melee weapons against Finn, as opposed to a blaster like most other troopers in the film.
In the film The Force Awakens a riot control stormtrooper confronts main character Finn, calls him a traitor, and duels Finn with lightsaber-resistant melee weaponry called a Z6 baton. The trooper seemingly defeats Finn before being shot and killed by Han Solo a few moments later.
In the official prequel book Before The Awakening it is revealed that the Stormtrooper's name was FN-2199, nicknamed "Nines". The Riot Stormtrooper trained with Finn, explaining why he singled out and attacked him in such and aggressive manner.
Following the film's release several image sharing boards, notably sites such as 4chan  and 8chan's /tv/ boards. On reddit several threads were about the character, including one where he was called "the best new character," which received 3,293 points (88% upvoted), and others that included several image edits of the character. On December 23rd, 2015, YouTuber Arby uploaded a video of the Stormtrooper spinning his riot melee weapon with Dead or Alive's You Spin Me Round (Like a Record) playing in the background (shown below).
 The Dork Side of the Force – Star Wars: The Force Awakens -- Daniel Craig's Stormtrooper's Designation Revealed
 Star Wars Official Website Meet FN-2199, A.K.A. TR-8R: The Stormtrooper Behind The Meme