This word comes from faggots who think they are going to be the next rapper of the generation, and make weird flexes. They aren't going anywhere and in life, usually they are white people trying to be black.
Gary: "That's mad lit, lets hang out next weekend, you should check out my new rap on soundcloud."
Me: "Eat shit gary, no one wants to listen to your shitty rap, you stupid cunt."
Basically, the male equivalent of chick lit. Books aimed at youngmen, typically with lots of action, adventure, and explosions.
The works of Tom Clancy, Michael Crichton, and Robert Ludlum would probably be considered dick lit, though plenty of older men like these guys a lot too.
Fiction, expecially literary fiction, written to promote philogynistic or gender-preferential political, philosphical or artistic agendas and attitudes. Frequently written by talented, but pissy novelistas, who pass all thoughts and words through the gender blender before publishing. Tendency to be sanctimonious and gender-issue-oriented; tendency to be boring to all except True Believers.
I'd rather swim the Channel with rocks in my pockets than read clit lit, you know, like stuff by Gertrude Stein, Woolf, Steinem, Dinensen, Mary McCarthy or Erica Jong.