You may have heard coworkers or acquaintances refer to an inconsequential or irrelevant point as a moot point, or maybe you’ve heard mute point instead. Fans of the TV show Friends may have heard a third variation: moo point (because, according to Joey, a cow’s opinion doesn’t matter). But which expression is correct, and what exactly does it mean?
The correct phrase is moot point. A moot point can be either an issue open for debate, or a matter of no practical value or importance because it’s hypothetical. The latter is more common in modern American English. The term comes from British law where it describes a hypothetical point of discussion used as teaching exercise for law students. This finds its roots in an early noun sense of moot: “an assembly of the people in early England exercising political, administrative, and judicial powers.” …… read more —> http://blog.dictionary.com/moot-point-vs-mute-point/