The summer between a student's senior year in high school and freshman year in college.
"Dude, did you see those hot freniors?"
"Yeah, they don't drink beer, but that'll change in a few months."
A Freshman-Senior hybrid. Freniors (a.k.a. Seshmen) like to act like Seniors and do everything that Seniors do. They throw parties, go to school dances and the teen center, join leadership, attend all football games, have a boyfriend, run the student section, do homework, and care about their career/college.
Shredder is a Frenior who is in leadership and enjoys school.
A senior in college who chooses to act like a freshman.
Well, yeah... but I'm still blacking out. Since, you know, I am a frenior.