"Language is always changing, evolving, and adapting to the needs of its users," writes Betty Birner in an op-ed or the Linguistic Society of America. "As long as the needs of language users continue to change, so will the language."

This is evident with a number of words that used to be common, but have fallen out of favor, replaced my more accurate, and in some cases, less offensive words.

As more attention is paid to previously marginalized and ignored people, some words are discarded for their lack of sensitivity. Others have their origins in racism, and become used less as those histories become more widely known. Here are a few that you might be using without any offensive intent:

1. "Third world"

The term "third world" is a Cold War anachronism developed to describe nations that were neither Western allies (the first world) or Communist satellites (the second world.)

It soon became a catch-all to refer to any country that wasn't aligned with either superpower; often receiving economic support for strategic considerations. But even this wasn't quite accurate.

"Although the phrase was widely used, it was never clear whether it was a clear category of analysis, or simply a convenient and rather vague label for an imprecise collection of states in the second half of the 20th century and some of the common problems that they faced," historian B.R. Tomlinson wrote in his 2003 essay "What was the Third World."

In a deep dive into the term, NPR blog Goats & Soda generally found that "developing world" is preferred among people who actually live and work in those nations. Even then, some scholars find it to be a reminder of colonialism, preferring to break countries up by income strata or geography.

2. "Prostitute"

Finding "sex worker" to be a more inclusive and accurate term, a campaign formed in 2014 asking the Associated Press to phase cut the word "prostitute."

Sex worker advocacy groups requested the change, claiming that "sex workers whose jobs you may feel fall under the heading ‘prostitute’ typically self-identify as something else entirely and this difference may actually be quite crucial to their jobs and livelihood."

These include people who "provide erotic services in the sex industry,” including escorts, strippers, pornographic film performers, and workers at brothels.

According to the Columbia Journalism Review, the AP did indeed stop using prostitute, but only in reference to minors, as the term implies someone “is voluntarily trading sex for money," which a minor can't legally consent to.

3. "Underprivileged"

The term technically refers to those who don't "enjoy the same standard of living or rights as the majority of people in a society," but has increasingly become a lazy shorthand to refer to any minority, regardless of economic status.

In 2014, college student Natasha Rodriguez was offered financial aid for "underprivileged students," despite not falling into that category. "Even though my family does not have a lot of money, we have always had enough to get by, and I have received an excellent education," she wrote in the Chronicle of Higher Education.

"Several colleges that had not even received information on my parents’ finances just assumed that I was underprivileged because I had checked "Latino/Hispanic" on their applications," she continues. Rodriguez suggests that simply labeling materials as "help for students in need" would be more accurate and less insulting.

As for what term to use to refer to people who truly are low-income, at least one policy expert for anti-poverty organization Oxfam International advises to keep it simple. "Poor. People are poor. More than 1.2 billion people are extremely poor. It’s awful."

4. "Gypped"

A term used for well over a century to denote being defrauded or swindled, gypped takes its origin from the nickname of the Romani people: gypsies. That term itself is known as an "exonym" — a term imposed upon an ethnic group by outsiders. In this case, the Romani emigrated out of India in the 11th Century and into Europe, where their dark features caused them to be mistaken for Egyptian.

At some point, their nomadic and insular lifestyle lead to Romani people getting a reputation as unscrupulous, godless, and barely civilized.

An the 1885 book called "Our Gipsies in City, Tent and Van" by Vernon Morwood is typical of how European people regarded the Romani — it calls them a "separate and mysterious" people, and at one point, derides their "questionable mode of life, their acts of dishonesty, and loose vagrant habits."

It was around the time of that book that "gypped" got its common usage attached, and it's still being used to this day, to the point where in 2013, mystery author Carol Higgins Clark had to apologize and retract a novel she'd titled "Gypped," not knowing the origin of the word.

5. "Sold down the river"

Another common phrase with an incredibly racist history, "sold down the river" has come to mean being betrayed or stabbed in the back. But it has a much more specific meaning: a slave being sold to a plantation at the southern end of the Mississippi or Ohio Rivers.

This was one of the major hubs for transporting slaves to the deep south, and the farther south you went, the worse the treatment and harder the work was for slaves. As journalist Lee Sandlin writes in his 2010 history, "Wicked River: The Mississippi When It Last Ran Wild," "the threat of being 'sold down the river' was seen as tantamount to a death sentence."

Many of these words and phrases are still incredibly common, and often aren't used in any racist or negative connotation. But all have better, more accurate, and less historically loaded alternatives.