Beclown

[Kai]

Verb. To make a complete idiot of oneself in public. To behave or speak in such a way, or to make a comment or express an opinion that is so profoundly witless, senseless and [obtuse], that you have [forever after] defined yourself as a person of [comical value] only. Never to be taken seriously again. Of worth only as an object of ridicule and derision.

[Zipporah Schumaker]

To [argue] loudly about [things] one does not [understand].