mid-15c., "one of a series of rings or loops which form a chain," probably from O.N. *hlenkr (cf. O.Swed. lænker "chain, link," Norw. lenke, Dan. lænke), from P.Gmc. *khlankijaz (cf. Ger. lenken "to bend, turn, lead," gelenk "articulation, joint, link," O.E. hlencan (pl.) "armor"), from PIE base *qleng- "to bend." The verb (late 14c.) is believed to be from the noun, though it is attested earlier. Missing link between man and apes dates to 1880.
programming, tool (link editor, linkage editor, link loader) A program that combines one or more files containing object code from separately compiled program modules into a single file containing loadable or executable code This process involves resolving references between the modules and fixing the relocation information used by the operating system kernel when loading the file into memory to run it. Under Unix, the linker is called "ld" and object files have filename extension .o (object), .so (shared object), or .lib (library), and the resulting executable is called "a.out" by default. (2001-10-13)