(CNN) Former CIA Director John Brennan tweeted Friday that President Donald Trump's administration is a failing "kakistocracy," causing a dramatic increase in online look-ups of the rarely used word.

"Your kakistocracy is collapsing after its lamentable journey," Brennan tweeted. "As the greatest Nation history has known, we have the opportunity to emerge from this nightmare stronger & more committed to ensuring a better life for all Americans, including those you have so tragically deceived."

Your kakistocracy is collapsing after its lamentable journey. As the greatest Nation history has known, we have the opportunity to emerge from this nightmare stronger & more committed to ensuring a better life for all Americans, including those you have so tragically deceived. https://t.co/eC6LATH2Gd — John O. Brennan (@JohnBrennan) April 13, 2018

Shortly after his tweet, Merriam-Webster wrote that the word, pronounced "kak-uh-STAH-kruh-see," means "government by the worst people."

According to the dictionary company, look-ups for the word increased by 13,700% on Friday.

Brennan's tweet was in response to attacks Trump made on former FBI Director James Comey. In two Friday morning tweets, Trump called Comey, whose new book discusses his tense relationship with the President and the Russia probe, a "proven LEAKER & LIAR."

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