Some serious fans even have a "look" - short, greasy hair, dyed black with bangs cut high on the forehead; glasses with thick black frames; thrift-store clothes and chunky black shoes; and make-up, on anyone.
Nathan Johnson didn't even know what emo meant until he looked it up on the internet a few months back. Now he has the clothes and the glasses and likes some of the bands considered "emo", Fugazi and Sunny Day Real Estate among them.
"It was as if all of the sudden emo was the `cool' phrase on everyone's lips," says Johnson, who's 25 and from Dallas. "Drop it among your more mainstream friends and you achieved a sort of instant cool."
Not that emo is necessarily new. The term has been around since the mid-1980s when bands such as Rites of Spring and Embrace emerged from the Washington punk scene with more introspective lyrics. Terms such as "pop-punk" or "emotional hardcore", or "emo-core" followed.
Now the music and the term are experiencing a rebirth.
And this time, the buzz is surrounding bands more popular with the mainstream.
Bands being called emo include The Promise Ring, The Get Up Kids, Pedro the Lion and Dashboard Confessional, whose repertoire includes such acoustic gut-wrenchers as Again I Go Unnoticed and Screaming Infidelities.
Even Jimmy Eat World - a mainstream band with definite punk roots but a decidedly poppy and sometimes even chipper sound - is making some emo lists.
Unhappy purists call much of it "mall emo" and worry that it's diluting the genre to the point of meaninglessness.
"It has become a garbage umbrella term," gripes Tom Joyce, a music fan from St. Paul, Minnesota.
Marissa DiMeo, an emo fan from New York, understands the angst over labeling music that she says mixes a few genres - punk, hardcore and "indie" rock, music from independent labels that's played more often on college and online stations than mainstream. But she does hear a common thread in emo.
"At its heart are emotionally charged lyrics - love songs with attitude and edge," the 24-year-old DiMeo says.
Alan Shum (18) agrees that emo is certainly not "stuff you could easily mosh to", a reference to the body-crashing mobs that often form next to punk concert stages.
"Emo is softer, gentler music, where artists sing about unrequited love or depression to more mellow guitar chords," says Shum, a student at New York University.
He says it can be so soft that his friends use the term to insult one another and hang it on any song they deem "unnecessarily emotional".
Shunning the label
Maybe that's why bands - even those getting attention for having an emo sound - are shunning the label.
Several, including Dashboard Confessional and The Get Up Kids, declined to be interviewed for this story.
Such a response isn't surprising to Jonah Matranga, a San Francisco-based singer-musician who performs as onelinedrawing - and who, in the late '90s, was dubbed the "emo king" by a British music publication.
A bit weary of the term, he says emo doesn't even mean what it once did - music that was "aggressively heart on the sleeve".
"Now it's more like 21st century Bay City Rollers. It's kind of like party music with a sour face on," says Matranga, who prefers to call what he's doing "eccentric pop".
Still, some up-and-coming bands wonder if the emo label might work to their advantage.
Critics had called the music of BE, an as yet unsigned Dallas band, everything from alternative rock to power pop. Then recently, one of them dubbed it "emo-esque".
Band members scratched their heads, but decided it was OK.
"If it truly means our music is open and emotional, then that's great," says Talley Summerlin, the group's lead singer.
"And if there's a way to be included in a movement that's getting attention, that can't hurt us, either."
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