On Thursday, The Economist released a lightly edited transcript of an interview it had with President Donald Trump, treasury secretary Steve Mnuchin, and National Economic Council director Gary Cohn.
During the interview, President Trump used the phrase "prime the pump," and claimed that he had come up with it "a couple of days ago."
Despite The Economist's editors' numerous assurances that they'd heard the phrase used before, Trump seemed determined to believe he'd invented it.
"Have you heard that expression used before?" he asked them. "Because I haven't heard it. I mean, I just...I came up with it a couple of days ago and I thought it was good."
Unfortunately for President Trump, the phrase "priming the pump" has been used in economics for a long time.
According to Merriam-Webster dictionary, it's been around since the early 19th century.
Merriam-Webseter never shies away from a chance to troll the president on Twitter, so they provided an explanation of the phrase's origins.
Twitter was quick to call Trump out on his bluff.
People also had some jokes.
Some Twitter users even shared the phrases they'd invented recently.
God save us all.