Covfefe - it's actually it is a real word of Yiddish origin, meaning...

A few people have asked me about President's Trump's tweet in which he used the word "covfefe." Most people think he meant to write "coverage" and they have had quite a bit of fun with it, but actually it is a real word of Yiddish origin, meaning "a futile search" or "a pointless and false quest." It was originally transliterated from the Hebrew as "kabfefe," whose etymology is "kab"—relating to the mystical Qabalah—and "fefe," which is a word for "butterfly." What Trump was actually saying in Yiddish tweet-speak was, "We are doing great things despite the press's negative and pointless search, aka fake news."

For those who are interested, the idea of "covfefe" comes from an old Yiddish tale about a foolish Sephardi rabbi who believed he was called to find and destroy the mythical and rare butterfly known as Benshariza, or "Lucifer butterfly"—a name that comes from "Helel ben Shahar," meaning "shining star" (see Isaiah 14:12; also see Ephesians 2:2, where Satan is called the "prince of the power of the air"). The rabbi claimed that the Benshariza was recognizable by a unique and disturbing pattern on its huge wings, which looked like the moon and star symbol of the god Ba'al-Hadad. He was convinced that this ominous creature housed "the spirit of Satan" and that if he could destroy it, he would free the world of evil.

His search became an obsession, driving him across Europe to catch countless butterflies, but all he really caught were rounds of derision. His travels took him from Iberia to Bucharest, then up to Moscow, and finally back to Europe again, where he met his doom in the Palatinate (southwestern Germany), in a little town called Cagelenstat.* There he came across a man who led him to believe that he had the beautiful butterfly in his possession but retorted, "Why, in the name of all things holy, would I hand it over to a little flitting fly-catcher on some stupid kabfefe!" The rabbi, exhausted and frustrated by his long travels, flew into a rage and lunged at him, who promptly drove a battle-axe into his skull and ended the meaningless quest. From that point on the word covfefe has been used to laugh at idiots in search of nothing.

*NOTE: It is likely mere coincidence that Cagelenstat is the original name of Kallstadt, Germany, which happens to be the birthplace of Friedrich Drumpf, the grandfather of Donald J. Trump. Friedrich, or Frederick, who became an American citizen in 1896, often advised his children, "Know what you want and follow your dream, but never get distracted by covfefe!"