L.C.L.Y. means: L.C.L.Y. L.C.L.Y. is in fact, in Chinese “lan si, lang yong”, which refers to a huge, lousy show off when she knows that he can’t accomplish something within his/her capabilities. When gossiping, this word is often used by asians and chinese. This is also used to express someone’s personality and attitude. (in Community Dictionary, added by Numbskull)