Used to describe a person or his/her actions as lazy, trashy, unattractive, materialistic, good-for-nothing, cheap, of lesser quality, or simply anything that the name-caller feels is below his/her own personal beliefs and values in life.
E.g., "that girl is so porch" could mean this girl did a number of contradictory things or lives her life in a number of ways including the following:
(1)dressing/acting like trash,
(2)not hooking up with you,
(3)blowing your uncle,
(4)believing anal sex = virginity,
(5)throwing up on herself at a bar,
(6)shitting herself at a party after taking too much GHB, or
(7)being lazy, spoiled and unproductive while being banked by daddy.
(This term is applicable to both men and women.)