Skid: (n.) A skid is technically a person who lives on the margins of society an shuns normal social contact.
But people usually just use it to describes punks and metalheads.

Canadian definition: Commonly used to refer to someone who stopped evolving, and bathing, during the 80's hair band era. Generally can be found wearing AC/DC muscle shirts, leather jackets, and sporting a mullet. The term "skid" is in part derived from "skid row", which is both a band enjoyed by those the term refers to, as well as their address. See also white trash and trailer park trash

Truely a Canadian definition:
.S.treet
.K.id
.I.n
.D.istress
Skids are those dirty bags who hang around in the darkest, dirtiest corners of the school raving about who they want to kill the most because they cant fit into society. Although the acronym may lead some to believe they are truely street kids, skids have homes and most likely families to go home to so choosing to be nasty is their own fault.

Brown shit stains on a pair of briefs, or a person who is discovered with(or suspected of having) said marks.

a person who is a skid mark on the underpants of society, hindering, rather than contributing, to it's advancement.

Skid: A wana be hacker who pretends to be a anon member. or has a Hack forums profile or SKID Forums and pretends to be the shit

Typically someone with notably poor hygiene habits, wearing shirts advertising for bands such as Slipknot, with a distinct odor, who smokes a good deal of marijuana, especially marijuana borrowed from others.