President Trump evidently doesn't know the definition of "press conference."

Last Friday, after two days of unusual engagement with the White House press corps, Trump promised to hold a "pretty big press conference" at the White House on Monday.

But the White House didn't set up any press conference. Instead, he gave a hastily-arranged speech without answering any questions.

Related: Trump answers 50-plus questions and promises a press conference

When he came before cameras a second time Monday, and CNN's Jim Acosta, who was in the room serving as pool reporter, asked about the lack of a presser, Trump said, "We had a press conference. We just had a press conference."

But he had not.

As Acosta pressed, asking if reporters could ask more questions, Trump turned to him and said, "I like real news, not fake news, you are fake news."

Acosta responded: "Haven't you spread a lot of fake news yourself, sir?"

Trump's declaration that "we had a press conference" seemed to confirm what some White House correspondents already surmised -- that Trump is counting any appearance in front of the press corps as a press conference.

Journalists, historians and past presidents all agree on a different definition. A "press conference" is a structured, seated event where the president fields a series of questions.

"Press availabilities" or "Q&A sessions" are more informal opportunities to ask questions of the president.

Trump's speeches on Monday met neither definition.

"It's not a press conference if you don't take questions from reporters," CNN White House reporter Kaitlan Collins said on the air after Trump claimed "we just had a press conference."

David Graham of The Atlantic remarked on Twitter that Trump "says confidently that there was a press conference that didn't happen, which is some aggressive gaslighting."

Acosta later called it a "flat-out falsehood."

Trump has held about a dozen relatively short joint press conferences with foreign heads of state since taking office in January. But he has not held a full-fledged solo press conference since February 16, breaking with decades of presidential precedent.

The presser drought has been getting more and more attention in recent weeks.

Some reporters thought Trump would hold a full-blown press conference before going on vacation in August, but he did not.

However, he did seem more accessible than usual while spending time at his private golf club in Bedminster, New Jersey last week.

Last Thursday and Friday Trump held a total of four press availabilities. He seemed eager to field questions from the journalists who were there.

At the fourth and final session, he said "we're going to have a pretty big press conference on Monday" -- which is why journalists wondered why he didn't follow through on Monday.