actually this originated from nigeria and has its interpretation in pidgin english. its translation is Laugh Wan Kill Me Die. this means, laughing to death or extremely funny.
Miss X:tina says i cant speak well, but did u u hear her poor speech yesterday??
Same as LWKM, but on a funnier scale. LWKMD: laugh wan kill me die. similar to lmfao, lmao, rotflmao, it's a more intensedescription of one's reaction to a joke.