Step aside, Mark Zuckerberg. There's a new record-breaking billionaire in town. 

Forbes on Tuesday named Kylie Jenner the "youngest self-made billionaire ever" in its annual list of the world's richest people. The 21-year-old cosmetics mogul reached the milestone at an age younger than Facebook's Zuckerberg, who was 23 when he earned the ranking. 

Other newcomers on Forbes' list include Spotify co-founders Daniel Ek and Martin Lorentzon, who are worth $2.3 billion and $3.1 billion, respectively. Snapchat's Evan Spiegel, 28, was listed among the top eight billionaires under 30, with a net worth of more than $2 billion.

Jenner is worth $1 billion, according to Forbes, thanks in part to her company Kylie Cosmetics signing an exclusive deal with Ulta Beauty last year. Kylie Cosmetics is worth around $900 million, Forbes estimates, and Jenner owns 100 percent of it. The money she's made from the business has helped push her into billionaire status. Bloomberg on Tuesday also named Jenner the world's youngest self-made billionaire, citing its daily ranking of the richest people.

The use of the word "self-made" has some people up in arms, given that Jenner comes from a wealthy family (the Kardashian-Jenner clan, for those not familiar). Dictionary.com, for one, wasn't having it. 

"Haven't we gone over this? Self-made: Having succeeded in life unaided," the account tweeted, along with a link to the definition of "self-made."

Forbes explained that it defines "self-made" as "someone who built a company or established a fortune on her own, rather than inheriting some or all of it." 

In 2014, the publication came up with a scoring system that ranks people on the Forbes 400 list of richest Americans on a scale of 1 to 10, based on "how self-made" they are. Someone who inherited everything they have gets a 1, whereas someone who didn't grow up with money and experienced hardships gets a 10, Forbes says. Jenner got a 7. 

"I didn't expect anything. I did not foresee the future," Jenner told Forbes about the ranking. "But [the recognition] feels really good. That's a nice pat on the back."

We bet it is.