You probably want to know about a "U-Boat", from "Unterseeboot", German for Undersea Boat, or, in other words, a submarine. So the answer is "underwater".
uboat
The Uboat was a submarine made by the Germans
It was the German way of saying "submarine" which properly should be called a "submersible." It is a shortening of "unterseeboot" to just uboat.
885.853199999 metres
Short for Unterseeboot - literally Undersea boat
In World WarII, the germans named it a uboat
UBoat
24 hours
The u boat can dive 200 to 250feet deep
yes
How many knots u have in ur grassy butt
The Allies sunk German Uboats. Uboat, not you-boat. Uboats stand for Unterseeboot - undersea boat.