Jarhead

[Sonia]

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.

[Tanya Shivari]

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.

[Sarah]

jar-head (n) a member of the United States Marine Corps..... OOooraaAAHH!!

[Little_Girl]

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.

[Zipporah Schumaker]

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.

[Dave Paprocki]

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 its 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 CANT.

[PussyCat]

Jarhead is a derogative term for US Marines based on the popular/common perception that they only follow orders and are incapable of individual thought as it is trained out of them in USMC basic.

[Vania]

A marine.

[Julian]

According to Heritage Press International: Jarhead: For roughly 50 years, sailors had little luck in their effort to insult Marines by calling them Gyrenes. So, during World War II sailors began referring to Marines as Jarheads. Presumably the high [collar on] the Marine [Dress Blues] uniform made a [Marines] head look like it was sticking out of the top of a Mason jar. Marines were not insulted. Instead, they embraced the new moniker as a term of utmost respect.

[Raeanne Dimick]

Term used by [US Marines], [meaning] [Marine]