Similar to, but not to be mistaken for "eye liner", it is the rimming of the male eye with usually a charcoal black color, and done voluntarily. Usually done by rock stars, emo
kids, and more recently hipsters
, it is a word used to masculinize a usually feminine product, thus making it more acceptable, at least for themselves. This is the main purpose for calling it by something other than simply eye liner
, a term used by either women, men who cross dress as women, or men who never actually wear it themselves.
It can also be used ironically by a second party, making fun of those belonging to the aforementioned groups, aka emos, wannabe rockstars, hipsters, etc.