[ad. G. U-boot, abbrev. of Unterseeboot ‘under-sea-boat.’] A submarine.
1915. F. A. Talbot, Submarines, xv. 186. The early ‘U’ boats are virtually duplicates of the boats supplied to the foregoing countries [Russia, Austria and Norway].
1918. Sat. Even. Post, CXC. 20 April, 15/2. The U-boat commander known to the fleet as ‘Mr. Kelly,’ a genial sport who had behaved like a real human being—a rare exception to the rule.
