U-16 may refer to one of the following German submarines.
SM U-16 or U-XVI was a or U-boat of the Austro-Hungarian Navy (Kaiserliche und Königliche Kriegsmarine or K.u. K. Kriegsmarine) during World War I. U-16 was constructed in Germany and shipped by rail to Pula where she was assembled and completed in September 1915.
A sports league is a group of sports teams that compete against each other in a specific sport.
A U engine is a piston engine made up of two separate straight engines (complete with separate crankshafts) joined by gears or chains.