Someone who claims to be better at something than they are.
“The young slender defense back, on that cool Autumn Thursday afternoon, with perfect form, burst into the air with a flair of quickness not seen by the other junior varsity scout team defenders. The vibrant defender, with his foam filled blocking arm pad glistening in the cool air against his sparkling helmet and matching shorts, tips the lofted fade route pass intended for the speedy all county varsity flanker. The flanker yells to the young sophomore, “You @##$%^$#%#$% #$#%^#$ Thursday All-American!” “What the @#$% are you doing?”
He said he knew java, but couldn't even define a string - what a Thursday All American.