President Trump tweeted a garbled late-night message that baffled everyone on Twitter. (Monica Akhtar/The Washington Post)

Only President Trump knows what was going through his mind — and his smartphone — when he tapped out a confusing statement containing the non-word “covfefe” just after midnight.

But that didn't stop members of Congress from opining on the definition of the most popular nonsense word of Trump's presidency.

For anybody sleeping or off Twitter at 12:06 a.m., Trump Standard Time, the president tweeted a bizarre sentence fragment that read, in its entirety: “Despite the constant negative press covfefe.”

He deleted the message early Wednesday morning, then tweeted again, just after 6 a.m., seemingly to make fun of his confounding “covfefe” tweet.

Who can figure out the true meaning of "covfefe" ??? Enjoy! — Donald J. Trump (@realDonaldTrump) May 31, 2017

Enjoy, indeed: As The Washington Post's Travis M. Andrews reported, the original “covfefe” tweet was retweeted more than 127,000 times and “liked” more than 162,000 times within six hours — “making it one of his most popular tweets in months. By then it had become a massive Internet joke.”

Among the people getting in on the action: other politicians in the nation's capital.

It got kind of ugly.

Some not-so-politely pointed out that “covfefe” was not an actual word, although nobody noted it was unbecoming of the president of the United States.

No Mr President covfefe is not a valid word. #POTUSplayingScrabble https://t.co/j89J4IGXUl — US Rep Brendan Boyle (@RepBrendanBoyle) May 31, 2017

Others offered definitions of what they thought the president was trying to convey.

Rep. Eric Swalwell (D-Calif.) pointed out that the Twitter faux pas came just hours after the nation learned that Trump's White House communications director had resigned (although Swalwell incorrectly said Mike Dubke was fired).

In other news, today the President fired his communications director. #DIY https://t.co/P5l5rPGXrr — Rep. Eric Swalwell (@RepSwalwell) May 31, 2017

Rep. Tim Ryan (D-Ohio) provided a salty sample definition:

If it was, Mr. President, I'd implore you to "Covfefe, already -- for goodness sake." — Congressman Tim Ryan (@RepTimRyan) May 31, 2017

And Rep. Jared Huffman (D-Calif.) took a shot at Trump's ongoing Russia scandal.

"Covfefe" is Russian for "please don't release those Kompromat tapes!" https://t.co/w7D33Nq0Pb — Rep. Jared Huffman (@JaredHuffman) May 31, 2017

Then there was Rep. Ted Lieu, the California Democrat who has become something of a political star by trying to out-tweet Trump.

His 37-character response to the tweet mocked 'round the world:

Yrsvjseubpihfcovswtvnjhgfefesxnklimnq — Ted Lieu (@tedlieu) May 31, 2017

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