The phrase "blatant falsehood" refers to a statement or claim that is obviously false or untrue. It means that the lie is easily noticeable or evident. Full definition
The pro-AB 32 speaker gave the familiar litany of issues, highly distorted some facts, and with blatant falsehoods thrown in. (wattsupwiththat.com)
But, like its predecessors, it airs blatant falsehoods about environmentalists and fits snugly into the corporate agenda. (climate-resistance.org)
The opposition New Patriotic Party (NPP) has described as blatant falsehood a claim by Radio Show Host Adakabre Frimpong Manso, that the party's Flagbearer Nana Akufo - Addo, once threatened his life and abused him because he was unhappy with his work on radio. (citifmonline.com)