1-on-1 Share definition Flag short for: personal discussion. means: 1 human talks to another human about private things like job, money or anything else. yesterday i had an 1-on-1 with my boss, we talked about the work. 1-on-1 by checkbobby.com July 1, 2009 0 0 Get merch Get the 1-on-1 mug. Buy Now — $32.95 See more merch