Brain Fart

A brain fart consists of verbalising the most incoherent, incongruent, inexplicable sentence one could ever hear, at any giving moment, usually resulting in the act of 'facepalming', proceeded by everyone who had the misfortune of being there to witness such unfathomable stupidity

Person A: Oh my god I've just had the most incredible brain fart...

Person B: That's so Maria Marcos de Macedo Sempiterno redacted of you!