One whose employement is generally more than the mandatory one-weekend-a-month, but less than a full-time employee of the National Guard. Guard Bums are sometimes students and can find enough money to get by working several days a month or periodically attending extra military courses for the Guard.
When asked what he does for a living, John replied "I'm just a Guard Bum until the next deployment comes along."
by Russellmania October 18, 2007