look up any word, like thot:
 
2.
Based off Superman, it's the inability to notice that someone wearing glasses and that person not wearing glasses are the same person.
Kyle: Tim? Is that you?

Tim: Yeah.

Kyle: Oh. I almost didn't notice you with your glasses on.

Tim: Yep. That's Clark Kent Syndrome for you.
by Rommer711 August 24, 2010
 
1.
Where a person (usually a guy) is barely worth attention with his glasses on, but when he takes them off you notice how very hot and attractive he is.
(sees guy without his glasses)
Girl 1: OMFG! Where are you glasses?!
Guy: I got contacts.
Girl 1: Aha..... (distracted)
Girl 2: (whispers) Clark Kent Syndrome.
Girl 1: Yeah, totally....
by 1mad_scientist December 01, 2009