RS: Sunday's news of the arrest of Saddam Hussein included some military lingo that has captured a lot of people's curiosity.

AA: "Spider hole," for example. Lieutenant General Ricardo Sanchez, the commander of American forces in Iraq, used that term to describe what troops had found.

SANCHEZ: "After uncovering the spider hole, a search was conducted, and Saddam Hussein was found hiding at the bottom of the hole."RS: Here in the United States, Sean Fitzpatrick happened to turn on his radio in the middle of a special report on the arrest. The amateur linguist knew the term "spider hole" -- but not from the dozens of dictionaries he's collected at his home in Pennsylvania.

AA: Sean Fitzpatrick served in Vietnam in the late 1960s, part of the time as an Army reporter and photographer. During the war, Viet Cong guerrillas used such holes to snipe at American troops. On Sunday, as he listened to the news, he's not sure which he heard first, the term itself or the description. But it didn't matter.

FITZPATRICK: "As soon as I heard the description, it matched up with 'spider hole,' that it was a hole in the ground for concealment that could be closed with some kind of concealing or camouflaged cover, the idea being that even if you were standing on it or next to it, you might not see that it was there, and yet the person inside could get out pretty quickly, because the cover was light and loosely fitted."RS: "And in this case it was Styrofoam with a rug on top."FITZPATRICK: "Right. And I'd known the term before. I think there was posting to the American Dialect Society list that had a news item from 1941 with a photo caption showing Marines, I believe, being taught to use spider holes. And you know, I didn't really know why, exactly why it was called a spider hole. I've seen it suggested that it's because there are certain kinds of spiders that build similar kinds of nests with a lid that the spider is able to pop out of and ambush prey. And that sort of makes sense, but exactly why it was called a spider as opposed to a covered foxhole or something like that, I don't know. Because that's basically what the idea is. It's a covered, concealed foxhole."AA: "So initially they referred to this hole as a spider hole, and we're hearing now 'rat hole.' What is the difference between a spider hole and a rat hole?"FITZPATRICK: "Oh, a rat hole is an old general civilian term. And I think it's just been applied to any kind of sordid refuge that a scoundrel or a rat hides in."RS: "Another expression we heard Sunday morning was 'high value target,' or HVT."FITZPATRICK: "Right. That was completely new to me. Actually I heard it just as 'HVT.' The colonel who was, I believe commanded that 600-man task force, kept referring to HVTs and I inferred pretty quickly that T stood for target, but I didn't know until quite a while later that HV stood for high value."AA: "And Saddam's codename that they were calling him was 'HVT one."FITZPATRICK: "Was it? OK ... "RS: "One term that we've been seeing is, and if you could explain it we'd appreciate it, is 'improvised explosive device.'"AA: "Or IED, as they also call it."RS: "What does that mean?"FITZPATRICK: "It means exactly what it says. It's an explosive device that has been manufactured in somebody's basement or somebody's garage rather than being manufactured specifically as an explosive, as a bomb. Or it's one that has been adapted. This seems also to be a pretty new term. It may even have been coined to deal with these roadside explosive devices which often use an actual explosive device, an unexploded bomb or an artillery shell that's been looted from a weapons repository and then set up with a fuse that can be detonated remotely."RS: Sean Fitzpatrick is a Vietnam veteran and former military journalist. He's now a technical writer and editor in the computer industry.

AA: And that's Wordmaster for this week.