A person (typically living in Colorado) that spends most of their times in the mountains skiing, snowboarding or other, thus putting chains on their tires often.
A Spy from Team Fortress 2, that doesn't know anything about spying, yet tries to "chain", these unintelligent individuals may also use a profile name, or rename their Conniver's Kunai, to a TF2Slurgi or tf2Klown references, or just downright steal their name/profile picture. These "people" may also think they are good because they 2 back to back stairstabs in players who installed the game a few days ago.
Person 1 : Dude this spy is so bad but he keeps going for the most obvious shit on me Person 2: Yeah that's a clear case of chainer syndrome
Someone who defines themself as a hot rodder but has never worked on a car before. They pay a shop to build a car and perform modification/maintenance instead of doing it themself. Often they dont even know anything about the car they had built.
Bob: "Thats a nice 32 3 window over there" Tim: "Yea, but the owners a gold chainer, he doesnt even know what engine hes running."