when a man stuffs a sock in his pants or wears a cup to impress women with his penis size he has a decepticock. Usually linked to a man with a tiny penis.
Girl 1: "So I went out with Jason last night and then we went back to his place....
Girl 2: OMG! how was he?
Girl 1: Totally a decepticock.
1. A cock that looks deceptively small, but once it's full sized can create a river of bludge.
2. A man who manages to consistently convince women he's sensitive, and predictably turns into a bastard when he has slept with them.
Baby don't be fooled, this decepticock will ruin you
Baby don't be fooled, he's a decepticock.