The word is blatherskite. Pronounced \BLATH-er-skahyt\. This word is a noun and is defined as
A person given to voluble, empty talk; nonsense.
Used in a sentence:
In the new year, be mindful of the cunning blatherskite who speaks convincing words trying to sway you from your path to God.
(1st John ch.4:vs.1-3)