1 - Commonly used to describe a once popular individual who has fallen from fame but is yet to realise it. Along with gross over-confidence, a certain lack of wit sums up the personality of such a character. If you engage in general conversation with a "sam" expect frequent interruptions in the form of childish outburst of random sounds. This seems a common ritual in the every-day life of a sam and is only found amusing only by the smattering of remaining cult-followers.
2 - In certain areas of Northeast Scotland can be used to describe a random person who looks similar to Dibs.
1 - "God i can't believe that guy keeps trying to talk to me, who does he think he is?"
"Relax, he's a total sam."
2 - "Woah i could have sworn i just saw Dibs."
"Nah, it would have been Sam."