A girl you who add's you on myspace. Then you look at her pictures and she has a fucked up grill and is wearing red lipstick looking like a transvestite and shit, she also has a fat cunt of a mole on her face
I was at a night club and a horse faced slut approached me and grinding against me when the new 50 track came on, it was gangsta rap and a horse faced slut, I ran home
a word that is given to a lot of people or celebs just simply as an exaggeration, because someone has a slightly long or evan oval shaped face/big teeth/buck teeth/gummy teeth or a goofy smile (probably about half the population then) loads of celebs out there from eva longoria to christina aguilera, prince william or leona lewis have been called a horse. i don't think they are considered ugly to most people, nor are horses themselves.
Pajama casual is a term used when working from home and preparing for a video conference. All business above the waist and your pajama pants down below.