A term meaning when a guy is in the best time of his life, where he looks the best, gets the hottest girls he will ever get and when your in his prime he will cherish those moments for the rest of his life because it will never happen again.
Alles: " Yo nelson got 5 girls last night , and every girl in our school thinks hes hot , hes set.

Joe: " Yeah i guess nel is in his prime "
by Joe Merks January 27, 2008
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