SLUMB is an acronym for when you can't be bothered to write out the whole thing whilst on the internet. as apossed to LOL, SLUMB is for those moments when you didn't actually laugh out loud. SLUMB stands for SILENTLY LAUGHING UNDER MY BREATH. As i have witnessed many times, people dont actually laugh out loud. maybe a chuckle or snigger under ones breath, hence SLUMB.
person one: did you see his hat today, it looked like a hotdog bun
person two: SLUMB. it did look like a hotdog roll.