adj., noun. shortened form of "skeptical" and/or "skeptic."
Sam: So did you hear about what happened to Sarah the other
day?
Amy: Yeah, but knowing how much she loves to lie, I'm a little
skepto about it...
Sam: Yeah, I don't really believe it either.
(derogatory) A person who thinks s/he is a true skeptic, but is not. (i.e., not open, objective, unbiased, etc. -- Often used against anti-conspiracy theory types)