Catchphrase used by pretentious douches to disregard anything slightly popular in an effort to feel unique and relevant while royally failing at both.
X: This song is good!
Y: It was good before everyone knew about it, now it's too mainstream.
X: Whatever.
Y: It was good before everyone knew about it, now it's too mainstream.
X: Whatever.
by Tsukinckney June 11, 2011
Get the Too Mainstreammug.