Yeah Mon Share definition Flag a phrase commonly used in Jamaica 1)said in confirmation of understanding statement 2)approval of action 1st person: I had some trouble with my car. 2nd person: yeah mon. Jamaican at a concert: YEAH MON! Yeah Mon by ccutemonkeygrl December 17, 2004 0 0 Get merch Get the Yeah Mon mug. Buy Now — $32.95 See more merch