A V-2 was a big rocket-bomb that Germany fired at cities in the last part of World War II, mostly at London and at Antwerp in Belgium. It is a proper name for one particular weapon, not a general word, so it almost always appears with a capital V and a hyphen: the V-2, a V-2 rocket, V-2s. You meet it in history books, museums, and documentaries, and hardly ever in daily talk. Two things made it frightening at the time. It flew very high and came down faster than sound, so there was no warning noise before it hit — the explosion came first, and the sound of it falling came after. And nothing could shoot it down. Its full German name means "revenge weapon two", because the Germans said they were paying Britain back for bombing German cities. The V-1 was the earlier one, a small flying machine with an engine that buzzed and then went silent before it dropped, so people did get a few seconds of warning. That is the main difference students should hold on to: V-1 buzzed, V-2 gave you nothing. The V-2 is also the reason we can say something else about it — it was the first man-made object to reach space, and the men who built it later built rockets for the American space programme. So it sits in two stories at once: a weapon that killed thousands, and the grandfather of the rockets that went to the moon. Writers often use it for that double feeling.