A made-up word that people use when they don't know the singularity of "alumnus" or plurality of "alumni." Often used openly by educational institutions.
Guy 1: Dude, that dude's an alum.
Guy 2: A what?
Guy 1: An alum, dude.
Guy 2: What's that?
Guy 1: You know, bro, he graduated from here.
Guy 2: Don't you mean he's an "alumnus"?
Guy 1: No, dude, wtf? Alum. Just like cact and fung.
Guy 2: A what?
Guy 1: An alum, dude.
Guy 2: What's that?
Guy 1: You know, bro, he graduated from here.
Guy 2: Don't you mean he's an "alumnus"?
Guy 1: No, dude, wtf? Alum. Just like cact and fung.
by PeacePig June 09, 2011

A graduate of a high school.
I graduated from Bremen High School in Midlothian, Illinois in 1990. My presence is still felt throughout the faculty.
by Saints September 24, 2003

Someone who is glad they graduated when they did. They are annoyed with the trashing of other Bullis Students. A Bullis alum thinks that the school is degenerating because the students are more interested in hurting each other than thinking about the community Bullis once had.
by Bullis Alum March 23, 2005

A rabid fan of The University of Alabama. These fans have never set foot in a college classroom, nor have they ever been to a game. These are the fans that spend their waking hours on chat forums of their rival schools spewing hatred. They hate your team more than they love their own.
Tyler01 is a typical sidewalk alum. He spends a good part of his day on Auburn message boards flaming the AU grads and putting down their alma mader, yet he never attended Alabama.
by AUalum91 September 07, 2008

by Holmezzzzz May 12, 2007

A rabid fan of The University of Alabama. These fans have never set foot in a college classroom, nor have they ever been to a game. These are the fans that spend their waking hours on chat forums of their rival schools spewing hatred.
Tyler01 is a typical sidewalk alum. He spends a good part of his day on Auburn message boards flaming the AU grads and putting down their alma mader, yet he never attended Alabama.
by AUalum91 September 08, 2008
