Some U.S. Food and Drug Administration scientists have been told to stop using the words "woman," "disabled" and "elderly" in external communications, two sources familiar with the matter said, part of a list of banned terms that a White House spokesman said had misinterpreted President Donald Trump's executive order.

A list with the file name "Prohibited words" has been circulating since at least last week in official work chats, according to two FDA scientists with direct knowledge of the matter who requested anonymity for fear of professional repercussions.

The list, which has not been previously reported, is sowing further confusion at an agency struggling with the Trump administration's sweeping firings.

The two scientists said that neither they nor their managers knew who issued the directive or why many of the more than two dozen words were included.

"I don't understand why we can't use a word like 'woman,'" one FDA source who received the list said. "The words on the list would make it almost impossible to do our jobs."

Another federal health agency was told in recent weeks to remove words such as gender, transgender, LGBT (lesbian, gay, bisexual and transgender) and nonbinary from its communications to ensure that they comply with executive orders that solely recognize male and female sex and eliminate diversity, equity and inclusion programs.

As a result of that directive, the U.S. Centers for Disease Control and Prevention took down publicly available health information, such as HIV datasets, and withdrew research papers that were being considered for publication in scientific journals for review by Trump appointees.

Public health experts said the removal of such terms threatens their ability to address all kinds of medical needs as they affect different groups, including those with HIV and sexually transmitted diseases.

The list circulating within the FDA is broader and includes words such as underrepresented, underserved, understudied, sex, identity, diverse, women, woman, promote, definition, continuum, ideology, self-assessed, special populations, elderly and disabled. It was not accompanied with an explanation.

The White House spokesman said that most of the words on the FDA list didn't need to be removed from communications. He said that an error may have resulted from FDA officials misinterpreting Trump's executive order against "gender ideology."

The spokesman said the FDA does need to prohibit use of the words gender, inclusion, identity, diversity, inter, intersex, equity, equitable, transgender and trans to comply with the order.

An FDA spokesman said the agency has no official list of banned words and declined to comment about the White House's contention that some words can't be used.

The two FDA sources said colleagues told them the list had originated within the Center for Devices and Radiological Health, which has more than 2,000 workers and is tasked with ensuring the safety and efficacy of medical devices.

The two sources said the restrictions on their speech, coupled with recent employee firings, would slow review processes for medical devices and prevent scientists' ability to question device safety before release to the public.

The White House spokesman said more than 1,000 workers at the FDA have been dismissed across divisions, out of a total workforce of nearly 20,000. The firings are part of mass layoffs across federal agencies by the Department of Government Efficiency led by billionaire entrepreneur Elon Musk.