MOO: In reality should be spelled M.O.O. which stands for MASTER OF the OBVIOUS
People who have an incessant urge to speak needlessly by pointing out things that any idiot knows already.
You are in an IMAX theater watching a Movie called "All about Beavers- the best Dam movie ever made"
The first shaot is a a beaver dam, and then they pull in closer and lo there is a beaver...And now some fool behind you says "LOOK IT'S A BEAVER!" and you say inder your breath "no shit Sherlock! another Moo!"