Since the beginning of this year, when licensed shops in California were granted permission to sell marijuana for recreational use, sellers have asked Gary Robbins, a science and technology reporter for the San Diego Union-Tribune, to be careful with his language. “They’ll send me an email saying, ‘Why did you use “pot” in that headline?’” Robbins says.

Cannabis has been legalized for recreational use in eight other states; it’s approved for medical use in 30. As more journalists cover the industry, worth billions of dollars, many have had to scrutinize the synonyms and slang they use—often at the urging of merchants. Some don’t want journalists to use the word “marijuana,” believing it has too dark a history. Others have a problem with “pot.” And some say that “weed” is too informal for a substance with medical applications.

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“I’ve been out to a couple of marijuana conferences and talked to a lot of people in the industry,” Kathleen Gray, a reporter who covers marijuana for the Detroit Free Press, says. “They prefer the use of ‘cannabis.’ One person sent me an email last week that said, ‘I really resent you using the term marijuana. That’s a pejorative. You should be using sativa and indica [cannabis strains].’ I emailed back and said, ‘I’m not going to do that.’” Gray, who went to college in the 1970s, prefers to go with what readers (including her former classmates) will recognize. “Most people outside of the industry know what ‘weed’ is,” Gray says. “I don’t use ‘pot shop,’ ” she adds. “I’ll call it a ‘marijuana dispensary’ or ‘medical marijuana dispensary.’ I’ll talk about ‘legal weed’ or ‘legal pot.’”

Technically, cannabis is the name of the plant from which both marijuana and hemp derive. Marijuana refers to the leaves and flowers that have psychotropic properties because of their high THC (tetrahydrocannabinol) concentration. Hemp, on the other hand, used in products such as clothing and rope, contains minimal THC.

According to Merriam-Webster, the word “marijuana” originated in Mexican Spanish for the medicinal varieties of cannabis, but how the word really came about is a matter of debate. The dictionary also says that the slang “pot” is “perhaps [a] modification of Mexican Spanish potiguaya (1938),” which came from potación de guaya, a drink made by steeping marijuana leaves in wine or brandy. People began calling marijuana “weed” because the plant grows so easily and rapidly.

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Industry professionals take aim at the term “marijuana” because, in the 1930s, when the US government began using it widely, it was to make the plant, brought by Mexican immigrants, sound foreign and frightening. (In 1937, Congress passed the Marihuana Tax Act, making it difficult to sell or use.) “We prefer to use the word cannabis because it is a respectful, scientific term that encompasses all the many different uses of the plant,” Harborside, a company that oversees California dispensaries, states on its website. Marijuana, the company argues, “is an emotional, pejorative term that has played a key role in creating the negative stigma that still tragically clings to this holistic, herbal medicine. Most cannabis users recognize the ‘M word’ as offensive, once they learn its history.”

Ricardo Baca runs Grasslands, a Colorado-based PR firm for cannabis and related industries, and previously led the marijuana beat team (and its vertical, “The Cannabist”) at the Denver Post. When he started his job as marijuana editor, his copy chief brought up the dark history of the word “marijuana.” “It was probably borne out of racism,” Baca says. “But it’s also the single most used term for this substance. In print, we used ‘marijuana,’ ‘cannabis,’ and ‘pot.’ Online, we didn’t care what we used.”

The marijuana industry, Baca adds, is “recovering from decades of unjust prohibition.” Some of his clients have asked him to use only the word “cannabis,” but he told them that ten times as many people search for “marijuana” on the internet as “cannabis.”

The Associated Press launched a “marijuana beat team” this year, consisting of 10 reporters and videographers. In May, the AP updated its style guide to provide guidance on the best terminology— “weed” is too colloquial, “pot” is fine—and later shared details on its preferred synonyms via Twitter:

Marijuana is the dried flower of the cannabis plant. “Cannabis” is the usual term outside North America; it and “pot” are also acceptable. Slang terms such as weed, reefer and ganja are acceptable in limited, colloquial cases or in quotations. (1/9) #APStyleChat — AP Stylebook (@APStylebook) June 13, 2018

Some governments and other entities prefer “cannabis” because of arguments that the term marijuana was popularized in the United States in the early 20th century to stoke anti-Mexican sentiment. (2/9) #APStyleChat — AP Stylebook (@APStylebook) June 13, 2018

“The spread of marijuana legalization for medical and recreational purposes was so rapid, and receiving so much coverage, that it became clear we and Stylebook users needed a more comprehensive set of guidelines,” Jeff McMillan, who serves on the AP’s five-member style committee, tells CJR in an email. “We considered not only industry preferences for the vocabulary used to cover the issue, but also scientific/medical and conversational approaches.”

Jon Gettman, an advocate for legal marijuana and former policy director for High Times, has mixed feelings. In 2015, he wrote a column for High Times saying, “The term ‘marijuana,’ given its history and the nature of prohibition, is downright nasty.” But lately Gettman, now an associate professor of criminal justice at Shenandoah University in Virginia, believes that marijuana is OK to use in articles, and that the term’s past misuse doesn’t make it a slur. Questions of word usage, he says, are “esoteric but not without importance.”

Noelle Crombie, of the Oregonian, has written about cannabis since 2012. “In the early days of coverage, I referred to it as ‘marijuana’ and sometimes as ‘pot,’” Crombie says. “In more recent years, I started using ‘cannabis’ and ‘marijuana’ interchangeably. Editors generally prefer that we refer to it as ‘marijuana’ since Oregon has a longstanding medical marijuana program. ‘Pot’ makes it into headlines for the sake of space.”

Robbins says he’s a bit puzzled about why he’s felt pushback only recently; after all, marijuana has been legal for medical use in California since 1996. “It feels like it’s been happening because it’s doing well,” Robbins says, referring to the cannabis boom. “It’s mainstream. They don’t want something to come up that detracts from a generally positive image. When stores started selling it [for recreational use] on January 1, no one knew what to expect. There hasn’t been a great deal of controversy since then. I see people of all ages buying it. A lot of the people there look like me. Baby Boomers. But I also see soccer moms buying it in the middle of the day.”

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Caren Lissner is the editor of the Hudson Reporter newspapers in New Jersey, and has written for The Washington Post and Atlantic.com. She has also written about journalism for Lit Hub. More of her writing can be found at carenlissner.com.