The Trump administration is waging a linguistic battle across official Washington, seeking to shift public perception of key policies by changing the way the federal government talks about climate change, scientific evidence and disadvantaged communities.

The push drew fresh attention after employees at the Department of Health and Human Services were told to avoid certain words — including "vulnerable," "entitlement" and "diversity" — when preparing requests for next year's budget. But the effort to disappear certain language and replace it with other terms is much broader, sparking resistance from career officials in federal agencies, outside experts and congressional Democrats.

Climate change, for example, has for months presented a linguistic minefield; multiple references to it have been purged repeatedly at the Environmental Protection Agency and the Interior Department. And in late summer, the Office of Juvenile Justice and Delinquency Prevention issued a "language guidance" document to employees and contractors bearing a column of words and phrases to be avoided, alongside a column of acceptable alternatives.

The one-page document recommends using "all youth" instead of "underserved youth," referring to crime as a "public issue/public concern" rather than a "public health issue/public health concern" and describing young people who commit crimes as "offenders" rather than "system-involved or justice-involved youths," according to a copy of the document obtained by The Washington Post.

The document also says to avoid the term "substance abuse disorder" in favor of "substance abuse issue" — a change that runs counter to efforts by experts to cast substance abuse as a disease. A Justice Department official, who was not authorized to speak publicly, said "the recommended terminology is intended to be more accurate and better reflect Justice Department priorities."

The desire to literally change the conversation in Washington is nothing new. For decades, incoming administrations have sought to advance their political agendas by rebranding existing initiatives and lifting new words to prominence in White House news releases.

After winning the election on a vow to end the wars in Iraq and Afghanistan, President Barack Obama dropped George W. Bush-era references to the "global war on terror," creating a new budget category labeled "overseas contingency operations." Meanwhile, Obama appointees at HHS abandoned the term "unaccompanied alien children," replacing it with "unaccompanied minors." (The current administration has reverted to "alien children," which is statutory language.)

But even in the context of this historical tug-of-war, the chasm between President Trump's top deputies and the federal workers charged with carrying out government policies appears particularly wide.

"The administration correctly understands that they are battling a hostile bureaucracy," said Barry Bennett, a GOP consultant who advised the president during last year's general election campaign. "The left likes to think that words are very important, particularly if it's words they don't like. Well, the right thinks that, too."

The debate erupted last week after HHS officials instructed employees to avoid certain words when drafting the department's fiscal 2019 budget request. A budget request describes an agency's work and mission, establishes priorities and sends a broad message about the direction of federal policy under an administration.

The instructions were part of a one-page "style guide," obtained by The Washington Post, that was included in a much longer budget guidance document. The style guide lists "vulnerable," "diversity" and "entitlement" as "words to avoid" when drafting the agency's fiscal 2019 budget request — except "when the terms are referenced within a legal citation or part of a title."

HHS spokesman Matt Lloyd confirmed that agency officials created the document but said they did not ban any words outright. The document was distributed to budget offices in the department's operating divisions, including the Centers for Disease Control and Prevention, National Institutes of Health and the Food and Drug Administration, an HHS official said.

At a budget meeting last week at the CDC in Atlanta, employees were also told to avoid four additional words and phrases: "fetus," "transgender," "evidence-based" and "science-based." The origin and intention of that verbal direction remains murky.

In an email, Lloyd said that "HHS and its agencies have not banned, prohibited or forbidden employees from using certain words." Instead, Lloyd said, employees have "misconstrued guidelines provided during routine discussions on the annual budget process. It was clearly stated to those involved in the discussions that the science should always drive the narrative."

But an official at another HHS agency who was briefed last week on use of "vulnerable," "diversity" and "entitlement" said the message was clear.

"It was interpreted as 'you are not to use these words in the budget narrative,' " said the official, who spoke on the condition of anonymity to discuss internal agency communications.

On Thursday, 10 Senate Democrats sent a letter to HHS acting secretary Eric Hargan asking for "clarification" about the language restrictions. If they are indeed in place, "we respectfully request that you immediately reverse these policies," the lawmakers wrote. "Words matter."

A group of 315 public health organizations also sought an explanation from Hargan. "As the nation's premier public health agency, the CDC cannot carry out its mission of improving the health and safety of all Americans when its staff are urged to avoid using basic phrases that are so intrinsic to public health," they wrote Thursday.

Rep. Tom Cole (R-Okla.), who chairs the House Appropriations subcommittee that oversees the HHS budget, interpreted the agency's guidance as "more silly than sinister," saying it shows the "bureaucracy trying to react to what they think the new administration wants to hear."

Agency officials are writing budgets "to make the case" for their priorities with both the Trump White House and the GOP-controlled Congress, Cole said, meaning they have to write in a way their audience "might actually read."

Cole noted that Obama administration officials referred constantly to climate change, assuming that would "unlock the door" to congressional funding. Now, Cole said, the term has essentially vanished from budget discussions across departments. A top EPA appointee has instructed officials to eliminate it in grant solicitations and has zeroed out funding for several initiatives that mention the term. And some career officials have cut it from public communications material for fear of angering Trump appointees.

Colorado College environmental science professor Miroslav Kummel, for example, had agreed to teach an "Introduction to Global Climate Change" class at the Florissant Fossil Beds National Monument this summer. But then a volunteer with the monument's Friends Group informed him that he would have to revise his syllabus.

"Unfortunately, I had to send your write-up to the National Park Service Climate Change office in Fort Collins for review," the volunteer wrote in an email. "The NPS has been told that Climate Change must not be part of the message. All references to it in future documents, orientation talks, etc. will not be allowed."

Kummel declared the instruction "not acceptable" and threatened to pull out. The group ultimately relented, and he went on with the class.

Park Service spokesman Jeremy K. Barnum said in an email that friends groups "are independent organizations" separate from the agency and officials were not aware of any effort by headquarters "to prevent the professor from delivering his presentation as planned."

Climate-related documents continue to be erased from Interior's website at a rapid clip: This month, the links to 92 national parks' climate action plans disappeared, according to the Environmental Data and Governance Initiative.

Meanwhile, the Justice Department's move to censor the discussion about juvenile justice has alarmed longtime advocates. Marcy Mistrett, chief executive of the Campaign for Youth Justice, who has seen the "language guidance" document, said referring to youths who have committed crimes only as "offenders" defines them too narrowly. "They are still children."

She added: "It's just very unusual to go that far into the weeds and actually handpick out words that are common words in a field."

Advocates said the new emphasis already is having an impact. A 2016 solicitation for proposals to provide mentoring to child victims of sex trafficking specifically cited LGBTQ youths, who make up a significant portion of the trafficked population, Mistrett said. This year, a similar solicitation for proposals contained no such mention.

Allies of the administration, while maintaining that no words have been banned outright under Trump, said word choices have also affected policies important to conservatives. Marjorie Dannenfelser, president of the antiabortion political action committee Susan B. Anthony List, argued that getting rid of the term "fetus," for example, would be a welcome change.

"The language we use to describe unborn human beings doesn't just follow cultural attitudes, it actually has shaped them and made unthinkable atrocities sound palatable," Dannenfelser said. "We are glad to see the administration working to humanize widely used terms that will shape the next generation's attitudes toward life."

Sarah Kaplan and Amy Goldstein contributed to this report.

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