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6.
The term "jarhead" comes from the shape of the Old Corps covers (hats) that were worn by Marines. The poster is assuming that it is derrogatory, but in fact Marines call each other jarhead as a matter of course.
by davewojta October 28, 2003
 
1.
A member of the United States Marine Corps. When used by civilians it could be considered derogatory, but it is used often among Marines.

The term originates from the "high and tight" haircut that many Marines have, which makes their head look like a jar. It did NOT originate from their uniform or cover.
"Oorah jarhead, semper fi!"
by Jay November 04, 2005
 
2.
A term used to describe a US Marine. Although some believe the term is of recent origin (Gulf War), it has been around for a long time (at least since World War II). It has nothing to do with haircuts, hats or headshape. It refers to the Marines propensity to follow orders, regardless of consequences or personal safety. Because of their single-minded willingness to put their duty before themselves, Marines are said to have jarheads...hard on the outside and empty on the inside. It is a good thing there are such men.
Running up a hill to take a machine gun nest is not something that most people would do, but a jarhead will do it everytime he is ordered.
by Headshot1k May 01, 2010
 
3.
The Slang term came about during WW2 as a slang term for a US Marine.
During the war some steel helmets were made by the Mason jar company.
Some Marines who were issues helmets made by Mason Jar co. were called Jar heads
by Donald Skirvin May 02, 2007
 
4.
jar-head (n) a member of the United States Marine Corps..... OOooraaAAHH!!
Well are you a jarhead?
by Koko February 10, 2003
 
5.
A word used by both ordinary people and marines to talk about marines. The term jarhead came out because of the very short hair cuts which resembles that of a jar.
1. Every single jarhead made the mistake of joining the corps.
2. I was made to be a jarhead, i was made to kick ass "Oorah".
by The Kevin December 19, 2005
 
7.
NOUN. A nick name for marines. Originated from the "high and tight" haircuts that make their heads look like jars.

The derrogatory version means That your head is like an empty jar, thus meaning stupid.

Marines call each other jarheads, so it's okay to say it if your a marine or a friend of a marine.
Kind of like the word "nigga." niggas can say it, YOU CAN'T.
1.(marine)Once a jarhead,always a jarhead.

2.(derrogatory) Your about as confused as a jarhead fuckin' a football.

3.(nigga) Wassup, my jarhead?

OR Thats one a funny-ass jarhead, right there!
by The Bugness December 31, 2010