LMSYD Share definition Flag Texting abbreviation for "Let Me Suck Your Dick." Used by thots who want the succ bad. Thot: Hey baby LMSYD Dude: Nah bitch you nasty LMSYD by ur mum ho February 14, 2019 0 0 Get merch Get the LMSYD mug. Buy Now — $32.95 See more merch