The full form of ROFLMAO is Rolling On Floor Laughing My Ass Off. It’s used on Miscellaneous ,Chat slang in Worldwide

In electronic communication, “ROFLMAO” is a common acronym for “Rolling on Floor, Laughing My A** Off.” Like many cultural curiosities of the Internet, it has become a part of modern English vernacular.

Example 1:

First user: “Oh, man, my boss just came to my cubicle. I was so embarrassed for him because his fly was open, and I didn’t have the courage to tell him. LOL!”

Second user: “ROFLMAO!”

The “laughing my a** off” phrase is similar to many other hyperbolic sayings where people do something so extreme that a part of their body falls off, whether it be a head, arm, or leg. Some examples of these sayings include “laughing my head off” and “writing my arm off.” LMAO is also part of several more elaborate acronyms, including LMFAO and ROFLMAO.