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5.
emo or screamo that is mainstream also often has extremely bad new cd. term coined when jimmy eat world got there ovaries taken out. thank you www.emogame.com
applies to such bands as all american rejects, jimmy eat world, dashboard confessional, thursday
by anonymous February 18, 2004
 
1.
A verb describing the small but strong population of people who love emo music, but also love other kinds of music as well. Mainstreamo people listen to Hawthorne Heights, The Used, My Chemical Romance, Senses Fail, Taking Back Sunday, etc. They do not paint their fingernails black, pierce their faces multiple times, die their hair, have lame haircuts, wear their belts with the buckle on the side, wear girls jeans, or sulk all day. You can love emo music and feel down sometimes without being full fledged "emo".
Max loves Hawthorne Heights, especially when they scream. He appreciate's when someone is that passionate about what their for, but that doesn't mean he's going to write sad poetry and tatoo the Used Heart on his arm. Max is Mainstreamo.
by Max the one and only April 04, 2006
 
2.
Those kids you see in the mall (usually around Hot Topic) that have multi-colored hair and listen to trendy dime-a-dozen bands that they and only they define as "emo".

Derived from the words "Mainstream" and "Emo".
Look a horde of depressed mainstreamos just showed up in the food court! Run for your lives!
by That guy you met that time April 18, 2011
 
3.
Any "emo" band that is blown up by advertising and has fallen into the "mainstream" by MTV and the likes.
"Dude, Atreyu has become so Main Streamo"

Underoath
Fall Out Boy
A Day to Remember
Atreyu
etc.
by Rican7 February 04, 2011
 
4.
Type of clothes that resemble what Emos would wear but marketed for a mass audience. Typically faux-vintage or of the Paul Frank variety.
Old Navy has a new line of mainstreamo clothes. They ain't foolin' no one.
by Vincent Goodwin July 09, 2005