Edwyna Estime was wearing a heavy, shapeless graduation gown. It was the color of charcoal and it reached all the way down to her ankles. And yet she had never felt hotter.

As she crossed the stage to accept her diploma, she heard the cheers from friends and family members. She was graduating from law school — and that, to her, was extremely hot.

“That was a three-year process,” said Ms. Estime, 26, who earned her degree this spring from the Shepard Broad College of Law at Nova Southeastern University in Davie, Fla. “Three years of waking up and not feeling hot for me to get to that one day where I’m like, ‘Wow, this is hot.’”

“This is what’s hot for me right now,” she added.

Ms. Estime is one of many who are expanding the definition of hotness, taking it beyond its former association with old notions of attractiveness. These days, being hot no longer pertains only to your physical appearance, but includes how you move through the world and how you see yourself.

Many of those pushing for a broader understanding of the term are also pushing back against the idea that you need to wait for confirmation from someone else before feeling justified in calling yourself hot. To them, hotness is a self-declaration, and that’s that. Hotness is no longer just in the eye of the beholder. It’s a mood. It’s a vibe.

Emily Sundberg, a 28-year-old editor and filmmaker in Brooklyn, was eating spaghetti when she had a realization: She was being hot.

There was nothing glamorous about it. It was just a solo weeknight dinner at the kitchen counter, and Ms. Sundberg was wearing workout clothes and glasses. But she felt moved to make a video of herself as she twirled the pasta strands onto a fork and succeeded in getting most of them all the way into her mouth. As she chewed, with Kanye West’s “Jail” blaring in the background, she stared into the lens with a blank expression.

Ms. Sundberg then posted the seven-second video to Instagram Stories. Within moments, comments began flooding into her DMs. Her selfie video had “activated some desire in my ‘reply guys,’” she said, using the term for people who provide unsolicited commentary on social media posts. “U snapped,” one wrote. “Marry me,” said another.

“You don’t have to ask for permission to be hot online,” Ms. Sundberg said. “You can take up space and perform and create your own power dynamics between yourself and your audience. I think being hot online is sort of pure and, debatably, what social media was originally for.”

Since May, women have been commemorating their graduation days by filling their social media timelines with photos of themselves in caps and gowns, along with captions alluding to their own hotness. “Real hot girls major in STEM,” read the mortarboard of one graduate of the University of Nevada, Las Vegas.

Ariana Nathani, a 25-year-old podcaster and event planner, has noticed the new usage of “hot.”

“There’s not one thing that defines what hot is,” she said. “It’s confidence. It’s the way you dress, the way that you present yourself to other people. That doesn’t mean you have to be the most symmetrically, physically perfect human being. I feel like that isn’t even as desirable anymore. Our definition of attraction and attractiveness has expanded so much.”

David Ko, an interior designer in Los Angeles, has a growing list of fairly banal phenomena that he defines as hot. They include tan lines, going on vacation, sugar-free candy, iced coffee, texting right back and trucker hats.

“There’s a campiness to it,” Mr. Ko, 30, said.

That ironic tone comes through loud and clear on social media. Since 2020, TikTok users have been posting videos of themselves doing activities that they deem hot to a snippet of Megan Thee Stallion’s feminist anthem “Girls in the Hood.” The videos begin with a snipped of audio taken from a Coach commercial in which Megan Thee Stallion explains that she can’t talk right now, because she is busy being hot. The activities shown in the videos include tapping on a laptop, doing homework on a Saturday night and cleaning crevices of student housing with sponges and brushes.

Nylon has reported on tinned fish as a “hot girl food,” and Vice noted the rise of the so-called “hot girl walk,” a phenomenon started by the TikTok influencer Mia Lind that encourages young women go on four-mile walks while remaining focused on self-affirming thoughts in three areas: what they are grateful for; their goals in life and how they plan to accomplish them; and how hot they are. “You may not think of any boys or any boy drama,” Ms. Lind said in the video that laid out the ground rules.

In an interview, she said that she wanted to “un-gatekeep” the feeling of being hot with her hot girl walk, taking it away from male-gaze arbiters who treat daily life like some kind of beauty pageant.

“Being hot is really accessible, more accessible than previously thought,” said Ms. Lind, who credited Megan Thee Stallion as an inspiration for the walk. “I think there’s a really big reclamation of the term hot.”

The hot girl walk has maintained its popularity since Ms. Lind posted her explanation video, which has accrued nearly three million views since, more than a year ago; the #hotgirlwalk hashtag has racked up more than 280 million views.

“The hot girl walk is a mind set,” said Ms. Lind, 23. “One of the main pillars of the hot girl walk is trying to build confidence. It’s an exercise in confronting that negative self-talk and feeling a sense of hotness.”

Ashlee Bennett, a psychotherapist in Melbourne, Australia, and the author of “The Art of Body Acceptance,” also sees the new usage of the word as a move toward self-empowerment.

“It’s a form of rebellion and a way to reclaim the narrative, especially from the damage done by fashion magazines of the ’90s and ’00s,” Ms. Bennett said in an email. “I think social media, even though it can have its downsides, has actually helped us broaden the concept of ‘what’s hot.’”

The word drifted away from merely denoting physical temperature around 1200 A.D., according to Kelly E. Wright, a sociolinguist and doctoral candidate at the University of Michigan. “Over time, the ways of being hot included passion, fury, frenzy, lust or deep interest in something,” Ms. Wright wrote in an email.

The word became a synonym for “popular” or “in demand” around 1909, she added, noting that Paris Hilton hit upon that meaning with her early-2000s catchphrase, “That’s hot.” In the 1920s, the word’s meaning was further extended to include sexual desirability.

Rachel Elizabeth Weissler, a researcher at the University of Oregon specializing in linguistics and Black studies, said that many words and phrases that become common in online discourse, including “hot,” “on fleek” and “kiki,” are rooted in BIPOC and queer communities. Over time they become co-opted and come to be seen as elements of “TikTok speak,” she said, a phenomenon she referred to as “semantic bleaching.”

She credited Megan Thee Stallion as a source of the memes promoting self-affirming messages for young women and girls, citing her 2020 song “Body.”

“We saw Meg come out with ‘Body’ during quarantine,” Dr. Weissler said, “and she said, ‘It’s going to be a hot girl summer. We’re going to be happy. We’re going to be confident women.’ A lot of our language change comes from women — it comes from Black people and also from people of color.”

For Ms. Estime, the recent law school graduate, the next hot occasion will come when she passes the bar exam.

“When I get those results in September,” she said, “that’ll be the hottest moment for me.”