FWIW, the "Boys" does not refer to young men, but to Captain Henry C. Boys, Assistant Superintendent of Design at Enfield. He was instrumental in the design of the big .55 rifle but died in 1937 just as it was officially adopted; it was named in his honor.
Capt. Boys was also largely responsible for the design of the Enfield revolver (Pistol, Revolver, No. 2, Mk I), which was adopted in 1932. Many collectors assume that the Enfield is simply a copy of the Webley Mk IV; in fact it is a quite different design, both better and cheaper to manufacture. Capt. Boys did his work well.
Jim