At 12:06 a.m. Wednesday, President Trump tweeted a strange sentence fragment.

"Despite the constant negative press covfefe," it read. That was it. It ended abruptly, as if someone stopped him, or he stopped himself, or perhaps he never meant to send it.

No, "covfefe" isn't a typo, at least, not on the part of the Washington Post.

It's a good guess that the word he was looking for was "coverage." It came out "covfefe." It was anybody's guess what words were meant to follow. "Despite the constant negative press covfefe," what?

Within five hours, it had been retweeted more than 115,000 times and "liked" more than 146,000 times — making it one of his most popular tweets in months.

By 5:48 a.m., the tweet had been deleted. (The Washington Post saved an image of it earlier in the night.)

Twenty minutes later, a new tweet replaced it:

Quickly, the "word" covfefe began trending. One company even appeared to have made a shirt with that odd combination of letters written across the front in bold, block letters.

Even the Philadelphia Police Department joined the trend:

"Don't talk to me until I've had my #covfefe," wrote one user.

"What's even the point of CNN if they're not going commercial-free with #covfefe coverage?" inquired another.

"The next time I go to Starbucks I'm gonna order a grande #covfefe," wrote one thirsty user.

The word "covfefe" does not appear in the Merriam-Webster dictionary. When searching for it on the company's website, the dictionary suggests "coffee," "coven," "cover," "covet," "covey" and "cuvee."

Clearly, it isn't an English word. Some tweets employing "covfefe" offer the option to translate it from Norwegian, though that appears to be a glitch of some sort. "Covfefe" does not appear to be a Norwegian word, either.

Desperate for a definition, some Twitter users came up with a few, such as coffee or a synonym to The Lion King's "hakuna matata." (It means no worries, for the rest of your days. Some would say it's a problem-free philosophy.)

Others suggested it might make a great band, or perhaps human, name.

Fusion even launched a poll asking others to weigh in on the strange word's pronunciation.

Some, meanwhile, defended Trump, pointing out that accidentally sending a half-typed tweet is a human error.

So many Twitter users weighed in on the apparent typo, it created two trending topics on Twitter and a Twitter moment.

The first trending topic was simply #covfefe. The other was "Rosebud," which refers to the famous dying words of Charles Kane in the film Citizen Kane. Its meaning remains a mystery until the end of the movie.

Other users, meanwhile, raced to tweet a "covfefe" joke.

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