Once, a young friend asked if I was "totally emo" back in high school. Sadly, or perhaps not sadly for me, my high school days predated the emo classification.
Emo is a word with many definitions, and variations thereof. Emo as my friend used it refers to a sub-culture of white middle class kids who dress like mannequins escaped from Hot Topic display windows and spend all of their time being or trying to be depressed. According to one of UrbanDictionary.com's definitions, an emo is "like a goth, only much less dark and much more Harry Potter." I guess that would have described me back in high school, if Harry Potter had been written and goth had been mainstream.
Emo is also a euphemism that Kids These Days use to describe one who self-injures.
The term, according to Wictionary.org, traces its roots to emocore, short for emotional hardcore, hardcore punk music "characterized by melodic musicianship and expressive, often confessional lyrics," according to Wikipedia.
Which is interesting because emo music, as opposed to emotional hardcore, is a sort of whiny, affected, melodramatic affair, which one Urban Dictionary user defines as "punk music on estrogen." Which is kind of funny because most musicians who could be described as emo are dudes.
Which is funny, because whiny, affected, melodramatic punk rock on estrogen could easily describe the grunge rock I was so fond of in high school.
Maybe I was totally emo.