NLSM Share definition Flag Nlsm means to shut the fuck up. When someone gets NLSM'd they feel mentally raped. If u got NLSM'd just leave life. Person 1 : Person 2 Person 2: yes Person 1 : Nlsm NLSM by NLSM January 4, 2022 0 0 Get merch Get the NLSM mug. Buy Now — $32.95 See more merch