WASHINGTON >> Covfefe (cuv-fey-fey) noun: A sure sign that President Donald Trump has regained control of his Twitter account.

For more than a week, the tweets from realDonaldTrump were, well, boring.

Throughout his first big foreign trip last week, Trump’s tweets had the vibe of a garden-variety politician: statements of solidarity with world leaders, retweets of his wife’s visits with students and sick children, video clips from arrival statements and formal ceremonies, photos of official dinners.

Yawn.

Well, Twitterverse, he’s back.

Starting with a wee-hours tweet that contained the mystifying nonword “covfefe,” Trump today unleashed a string of tweets that showed the president was holding nothing back, on matters both trivial and consequential.

He lashed out at the government’s Russia investigation as a “Witch Hunt!”

He scolded celebrity Kathy Griffin for a video that showed what looked like Trump’s severed head: “My children, especially my 11-year-old son, Barron, are having a hard time with this. Sick!”

He stoked suspense about whether he’ll pull the U.S. out of an international climate change agreement: “I will be announcing my decision on the Paris Accord over the next few days. MAKE AMERICA GREAT AGAIN!”

And he resumed his attacks on his 2016 presidential rival, tweeting, “Crooked Hillary Clinton now blames everybody but herself, refuses to say she was a terrible candidate.”

But the internet flipped out over this baffling post-midnight tweet (later deleted): “Despite the constant negative press covfefe”

With that, Trump’s twitter feed went silent for the next five and a half hours.

Was it tweetus incompletus? Did the tweeter-in-chief fall asleep at the keyboard?

Former Obama White House videographer Arun Chaudhary tweeted this theory: “As a human with sleeping issues and a former WH staffer I can safely say Ambien is the source of #covfefe.”

And what was Trump trying to say, anyway?

Was it the start of a rant against “negative press coverage” that somehow went awry?

At 6:09 a.m., Trump’s twitter feed came alive again with this playful challenge: “Who can figure out the true meaning of “covfefe” ??? Enjoy!”

Team Twitter already had gone into overdrive trying to fill in the blanks, floating both silly and serious scenarios.

One user tweeted that New York’s hottest nightclub is #Covfefe. “It has everything: Russian entanglements, spray tans, creepy handshakes, surprise trade wars.”

Another suggested “covfefe” was becoming a popular name for babies in states that voted for Trump. Silicon Valley executive Andrew Crow went so far as to change his last name on Twitter to “Covfefe.” Jimmy Kimmel lamented that he’ll never write anything funnier than the term.

Conservative radio host Laura Ingraham had a pointed political theory: “It’s so bad—the collusion b/t the Dems & the press, the establ vs the ppl, that we needed a new word to describe it all. #Covfefe!”

Even Clinton weighed in. “It was a hidden message to the Russians,” she joked at a technology conference today in Los Angeles.

And later, she responded to Trump’s “Crooked Hillary” jab by tweeting, “People in covfefe houses shouldn’t throw covfefe.”

Republican strategist Liz Mair, by contrast, saw it as a way for the White House to create a distraction from negative stories about the president.

“The #covfefe stuff is funny, but everyone gets that this is one way Trump will detract from some really bad news for him last night, yes?” she tweeted.

Whatever the back story, there was no disputing that with “covfefe,” the presidential tweeter was back in full.

After all, Trump did once say he had “the best words.”