A spedstain is usually used to refer to someone who doesn’t know a basic thing, or something that is obvious to anyone around them. Commonly used out of rage.
Brody: GET IT.
Claire: Where is it?
Brody: IT’S RIGHT THERE YOU SPEDSTAIN.
A small piece of information. Derived from the word ken, used often in the scottish language and is synonymous with knowledge.
Person 1: "Hey I don't get this shit. How do you solve this problem?"
Person 2: "I got that one. Give me some kenlets on this assignment and I'll help you w/ that one."