n. A journalist inserted into a military unit to provide coverage of that unit during a battle or war.
Other Forms
For a week in early February, a flabby brigade of 57 reporters, photographers and network talking heads (9 of them women) gathered at the Quantico Marine Corps training base in Virginia, where we learned how to improve our chances of surviving a war with Iraq. As prospective embeds — journalists planted among America's fighting forces — we were given a crash course in all things military: how to dead-reckon (navigation with a compass), how to create the perfect field latrine (shovel, wooden planks, baby wipes) and what to do with a comrade whose viscera are spilling out (don't try to put them back inside; just place the innards on the stomach and utter reassuring words).
—Andrew Jacobs, “My Week at Embed Boot Camp,” The New York Times, March 02, 2003
The Gulf War was arguably the last World War II-style conventional war, with armored front lines pushing in one direction toward a national capital. Many military and political experts expect a Gulf War II to be more ragged, chaotic and nonlinear, rather like Vietnam or Afghanistan short bursts of battle followed by long periods of waiting, with troops spread thin throughout a whole country and its geographical neighbors.

The flow of news is harder to control during this sort of war, which may be one of the reasons the Pentagon has loosened restrictions on the press. During Gulf War I, military officers herded a select group of reporters around in carefully supervised "pools" and combed through every word and image they produced to make sure they flattered the war effort. If a second war breaks out, reporters will be attached to individual combat units.

Would-be war correspondents, nicknamed "embeds," are being put through reporter boot camps, supervised by U.S. military personnel or by private companies staffed with ex-soldiers.
—Matt Zoller Seitz, “TV News Gears Up for Next-Generation War Coverage,” Newhouse News Service, February 11, 2003
2002 (earliest)
This isn't really a question so much as a request. The number of embeds over in the theater have dwindled to a very small trickle. One that was ongoing last week was a Stars & Stripes reporter. The group that he was with when they went to the helicopter crash scene, he was literally in the helicopter, then pulled out at the last minute.

So we would like there to be more embeds over there, and when there are embeds that reporters and people with them understand ground rules, and we understood that we were there for the good, the bad and the ugly.
—Sandy Johnson, “DoD News Briefing,” M2 Presswire, June 21, 2002