U.S. Marine Corps Dictionary


I & I

Inspector and Instructor. The active duty cadre assigned to a Marine Corps reserve unit.

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I Corps

(Vietnam) Pronounced eye-corps. The northernmost of four corps areas in South Vietnam. I Corps was the province of the U. S. Marines while II, III and IV Corps were US Army areas.

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Military slang term for the Middle East. Combines Iraq with the suffix of “istan which applies to 90% of the Muslim countries in the Middle East and central Asia, i.e. Afghanistan, Turkmenistan, Uzbekistan, Pakistan, etc.

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(see Grass.) (origin) Vietnam

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Irish Pennant

A string hanging randomly from a Marine”s uniform. Longer ones are sometimes called rappelling ropes or cables. A squared away Marine will be free of Irish pennants, particularly at an inspection.

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Inspector General.

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Iron Mike

A statue of a World War I Marine at Quantico, VA with a copy on Parris Island, SC. (background) The original was made by the government of France to thank the Americans for their aid in World War I. When it was presented to General Pershing he noticed that the Doughboy holding aloft an M1911 A1 pistol had a Marine Corps emblem on his helmet. Pershing refused to accept the sculpture and it was given to the Marines.

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Ike Jacket

The term was not authorized in the Marine Corps and when used would subject a Marine to a reprimand. (background) Marines remembered General Eisenhower’s comment that he would have no Marines in Europe (having forgotten that his reserve force in Northern Ireland was Marine and paying no attention to the OSS personnel in the theater). A uniform jacket of similar design was authorized just after World War II and continued into the early 1960s. It was a forest green fabric with a faux belt and no skirt below the belt. (see Battle Jacket.)

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Incentive Training.

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Night artillery fire used to illuminate an area using a phosphorous filament suspended by a parachute.

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Infantry Training Battalion. (see School of Infantry)

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Improvise, Adapt and Overcome

An unofficial mantra of the Marine Corps, based on the fact that the Corps generally received Army hand-me-downs and the troops were poorly equipped. Despite this, the Marine Corps has been successful mostly because of the creativity of its people and their success-based attitude.

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Infantry Training Regiment. The old name for Infantry Training Battalion.

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Individual Memorandum of Receipt. The form used to issue 782 Gear.

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Itty Bitty Gook Boats

Small Vietnamese fishing junks in the DaNang area. Early in the 1960s they were prevalent but by the end of the decade they were nearly extinct. (origin) Vietnam

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In Country

(Vietnam) Serving (or having served) in Vietnam. (Iraq) Serving (or having served) in Iraq. Often used to refer to any current combat zone.

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An artillery shell that burns upon impact, usually stuffed with white phosphorous.

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Incentive Training

Physical exercise used as a punishment to instill motivation, particularly in a Marine recruit during boot camp. (synonyms) Quarterdecking or being pitted (as outside it is usually conducted in a special sand pit designed for the purpose)

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An alert that something is coming at you, often enemy fire or artillery.

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Indian Territory

Enemy-held areas. (origin) Vietnam

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Initial Strength Test

A physical test given early in the training of a recruit to determine if the recruit meets minimum fitness standards and to set a baseline for measuring progress.

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About DevilDogCorps.com

DevilDogCorps.com is an unofficial online dictionary of terms and acronyms commonly used within the United States Marine Corps.