Largely unknown outside of New England, "coffee milk" has made a splash this fall thanks to Dunkin's limited-time product, the "Dunkalatte." 

A typical latte combines a milk base with espresso. The Dunkalette, for its part, combines coffee milk and espresso. 

The addition of coffee milk to the drink meant that Dunkin' had to not only market the Dunkalatte across the United States, but also let others know exactly what the phrase "coffee milk" meant. 

NATIONAL COFFEE DAY: WHERE TO FIND THE BEST DEALS FOR FREE DRINKS

"When we first created the Dunkalatte, we knew we had something special on our hands, but introducing coffee milk, an unfamiliar concept to most, was a challenge," Jill McVicar Nelson, chief marketing officer at Dunkin’, said in a statement to Fox News Digital. 

News of the Dunkalatte's coffee milk base even prompted politicians to express their excitement.

Rhode Island Gov. Dan McKee (D) posted a "galaxy brain" meme on X in late August, saying that the combination of coffee milk and Dunkin's iced coffee had the "largest brain."

Gov. Maura Healey (D-Mass.), a fellow New Englander, then quoted McKee's meme.

She added this commentary: "The non-New England mind cannot comprehend this." 

But what is coffee milk? 

And why is it so popular in New England yet virtually unheard of everywhere else? 

Here's a splash of background. 

Coffee milk is created by adding coffee-flavored syrup to milk, Eli Berkowitz, CEO of Little Rhody Foods, told Fox News Digital in a phone interview. 

CHICORY AN ALL-NATURAL ALTERNATIVE TO CHEMICALLY DECAFFEINATED COFFEE, SAYS HOMESTEADER

It's similar to how chocolate syrup or strawberry syrup can be added to milk to make chocolate and strawberry milk. 

Little Rhody Foods is a distributor of the three major brands of coffee syrup: Autocrat, Coffee Time, and Eclipse. This syrup is not brewed coffee, but it does contain coffee extract, according to its ingredients list. 

"It's a Rhode Island tradition," said Berkowitz. "Once you leave [Rhode Island], when you head to New York — they all think you're talking about something else. They have no idea." 

He added, "It's just bizarre how it's only a Rhode Island thing."

Berkowitz, like many people in Rhode Island, has been drinking coffee milk since he was a child. 

"It's just been a New England staple for whatever the reason was. That's how we all grew up as kids," he said. "I'm 65 and that's what I always wanted."

DARK MILK VS. MILK CHOCOLATE: AMERICANS LOVE ONE MORE THAN THE OTHER, BUT WHICH IS ‘BETTER’ FOR YOU?

Coffee milk, said Berkowitz, does not have the exact flavor profile of a regular hot cup of coffee.

"[There's] just a sweet taste to it. That's what it is," he said. 

While there is caffeine in the product, it differs by brand, Berkowitz noted. 

Still, its surface similarities to the beverage typically consumed by older people are likely why it was so popular among kids, he said. 

MAINE LOBSTER FISHERMAN REVEALS WHY THE CRUSTACEANS SHE CATCHES TASTE 'SWEETER,' 'BETTER'

"I think when kids were growing up, mom and dad were having a cup of coffee — [it was] like, ‘Can I have that?’" he said. 

Instead of coffee, parents would tell their children to have coffee milk, as "it's got that darker color to it." 

CLICK HERE TO SIGN UP FOR OUR LIFESTYLE NEWSLETTER

"I think it was one way to get kids to drink more milk," said Berkowitz. 

"If kids didn't like plain milk, it was kind of sweetened up with [syrup]." 

On June 29, 1993, coffee milk was adopted as the "State Drink" of Rhode Island, the Rhode Island Secretary of State's website notes. 

For more Lifestyle articles, visit www.foxnews.com/lifestyle

Deputy Secretary of State Rob Rock described himself as a "huge coffee milk fan." 

In an email to Fox News Digital, Rock shared his favorite way of preparing the beverage. 

"Coffee milk tastes best with the right balance of Autocrat Coffee Syrup and milk, preferably 2%," he said. 

"It tastes like melted coffee ice cream!"