megatron syndrome 

act like a total dick to a family member or friend for no reason just for the hell of it. usually yelling or swearing for no reason so you can get your point across.

Ryan: FUCKKKK!!!! AAAAGH!
Austin: what are you talking about?
Frankie: dont mind him he has megatron syndrome
Austin: wow what a Asshole!
Ryan: DO AS I COMMAND!
Frankie: NEVER DICK WEED

megatron syndrome by Orlando Paulson March 1, 2011