The bill, which passed the Senate in May and was sponsored by Sens. Kent Conrad (D-N.D.) and Mike Crapo (R-Idaho), to "reflect the 21st-century understanding of mental illness and disease, and that the continued use of this pejorative term has no place in the U.S. Code." It could be passed by the House as soon as Tuesday.
The term "lunatic" actually appears in the very first chapter of the first title of U.S. Code, which provides basic definitions of words to denote number, gender and other terms used to discuss people on whom the laws apply.
It reads: "the words “insane” and “insane person” and “lunatic” shall include every idiot, lunatic, insane person, and person non compos mentis."
The recent bill is not the first attempt at improving the language of U.S. law: "mental retardation" and "intellectual disabilities" were removed from U.S. code in 2010.
According to the BBC, advocates lobby for the removal of words such as "lunatic" for more than an adventure in political correctness, but in fact to remove a stigma faced by those who live with mental illnesses and developmental disabilities.
"The written laws of the US, let alone the ones at the state level, are official pronouncements," Bob Carolla, a spokesman for the National Alliance on Mental Illness, told the BBC.
"It can show up in court proceedings, it can show up in any kind of legal citation or boilerplate. Anyone with a mental illness is never going to know when they're going to be slapped in the face by it, and it's coming in a very official context."
The word "lunatic" precedes modern understanding of mental illness--in fact, it's older than the English language, coming from the Latin "lunaticus," describing a kind of insanity supposedly dependent on the phases of the moon.