mainster 

a hipster monster, a person that goes the extra mile to be a hipster and ends up looking like a dumbass

guy 1:yo bro i was wearing pink socks before anyone bro!

guy 2: haha nah bro you a mainster!!!!

mainster by freshness/doom2036 November 7, 2011

Mainster 

People who are mainstream because being hipster is to mainstream.

Derek (being a mainster) wore skinny jeans, Volcom apparel, and Vans skating shoes.

Mainster by LandOfTheEast January 24, 2015

mansterooni 

A person who slaps their thighs together

Some sluts are Mansteroonis

mansterooni by Frankane April 13, 2015

Best Manister 

When the Best Man of a wedding is also the officiant

Jay surprised everyone at the wedding by making his brother the best manister.

Best Manister by Kizzler May 6, 2013

mainstream meme 

When a meme has become so popular that it appears on the news, TV, or anything else outside of message boards. When this happens, it is deemed too popular and forever called "OLD".

Rick Rolling has been a mainstream meme for a very long time. Cut it out.

mainstream meme by deathwish124 May 24, 2009

Mainstream music 

Music that always plays on the radio and the TV, and is on the top 40 list on every music software like iTunes and Spotify. It is quick-made on a computer, usually featuring not very good but good looking musicians (if they can be called that) and it is un-original and boring. People without any taste in music listen to it because it's easy to find and everyone else listen to it, so then they don't need to worry about being considered "different". Mainstream music songs usually stay on the top-lists for a couple of months or maybe a year, and then they're gone. Also, people who listen to it usually would call a 2 year old song "very old", though bands like Led Zeppelin still rock anyone's brains out with their songs from the seventees.

Annoying teen girl: "Oh my god, have you heard that new Rihanna song? I love it!"

A month later, someone puts on the same mainstream music song

Same annoying chick: "Eww that song is old and outdated, turn it off"

Mainstream music by rocknroller2012 December 17, 2012

Mainstream crap 

Music that focuses on getting stuck in your head and becoming so ubiquitus that you are forced to like it or else you will have clinical depression from hearing it so much. This music is almost always made by humans who are often called musicians (but in all truth, are not musicians) who manipulate their image for monotary reasons. This music often focuses on sounding much more technological than musical. Much pop and hip-hop to enter the top 40 has been mainstream crap since the '00's.

person 1: Man, Lady Gaga, The BEP, and other mainstream crap has been all over the place, it makes me want to commit suicide

person 2: I use to think the same thing, but now the music has grown on me

person 1: Nooooooooo! You failed in the battle to not get that music stuck in your head to the point where you have to like it! What has become of this world

Mainstream crap by Suteer Yarchaz January 18, 2010