Chick-fil-A is right coded. “Rent” and “Hamilton” are left coded. Comedy and wrestling are right coded. Independent movie theaters and capoeira are left coded. “Yellowstone” is right coded and “White Lotus” is left. There’s a case for the HBO show “Girls” being right coded. “Superbad” is a little unclear.

People have often signaled their values in the shows they watch (“The West Wing”), clothes they wear (white pantsuits) and restaurants they frequent. But it has become wildly popular in recent years, and especially in recent months, to read cultural tea leaves with the word “coded.” In group chats, on Reddit and on X, we’re calling anything and everything right or left “coded.” It’s like playing a game of charades, gesturing at the qualities a certain celebrity or bar or podcast has without saying exactly what you mean. Linguists notice it too, pointing to Google data that shows a spike in the use of “coded,” with its current meaning, since the 2010s.

“It’s a way of acknowledging that even when something isn’t literally conservative, it can still convey conservativeness,” said Lal Zimman, an associate professor of linguistics at the University of California, Santa Barbara.

To understand why the word “coded” spread — why “The Big Short” is millennial coded and Timothée Chalamet is Proust coded and “Yellowstone” is NIMBY coded — requires going back to tree trunks in ancient Rome. That is where the word “code” itself was born, according to the historical linguist Danny Bate.

Tracing the history of the word, Mr. Bate found that an etymon had been used to refer to tree trunks. Those trees were chopped into pieces that were used to write laws on, which led to the term “code of law.” In the early 1800s, in another twist, European military leaders started using “code” to refer to the secrets of military life that were understood but not made explicit. In the 1960s, in academia, “coded” became a useful way of discerning subtle messages about identity groups, calling a doll “girl coded,” for example. And in the 2010s, in online forums, fans of the TV show “Steven Universe” gave the word “coded” its modern meaning, talking about how cartoon characters could be “coded” as gay.

If the words we use both reflect and reshape the upside-down moment we’re in, “coded” is a sign of the times. It sorts the shifty, amorphousness of culture into the hard and fast lines of our polarized politics.