Just midnight local time in Washington, Donald Trump’s Twitter account @realDonaldTrump posted: “Despite the constant negative press covfefe.”
With no correction or further explanation issued, the made-up word #Covfefe was soon trending on Twitter as users debated what he could have meant.
The senseless message was retweeted more than 125,000 times and was widely reported in the mainstream press overnight.
This morning the tweet was deleted. At 6.09am local time in Washtington, Mr Trump tweeted: "Who can figure out the true meaning of "covfefe" ??? Enjoy!"
Last night the bizarre post even sparked concerns that Mr Trump might have stopped halfway through posting the tweet due to some kind of emergency.
Emily Nussbaum, the New Yorker television critic, posted: “What if this is it. That is his final tweet & the rest of history stops.”
There is no such word as “covfefe” but Mr Trump may have made the typo while starting to criticise negative media coverage and ‘fake news’.
Many Twitter users turned to the Merriam-Wesbter Dictionary for an explanation.
But @MerriamWebster could not provide an answer and tweeted: “Wakes up. Checks Twitter. Uh… Lookups fo… Regrets checking Twitter. Goes back to bed.”
������ Lookups fo…
Regrets checking Twitter.
Goes back to bed.
— Merriam-Webster (@MerriamWebster) May 31, 2017
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Mr Trump's tweet was widely mocked overnight with Twitter uses around the world making jokes about covfefe. Some compared it to coffee.
One Twitter user said: "That feeling when you wake up and the world has gone #covfefe."
Another said: "#Covfefe. Glorious new name for baby girls."
One frustrated person tweeted: "Like I don't have enough problems in my life and now I have to figure out the true meaning of #covfefe."
Someone else said: "#Covfefe ~ help us understand this alien language!"
But a fan of the made-up word said: "All we are saying, is give #covfefe a chance…"
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