Diploma mill
A diploma mill is a term for an organization that provides a certificate that indicates educational achievement for a fee. Strictly, the term has some legal implication. In the United States, that meaning was codified in the 1950's in the wake of the GI Bill, which provided government subsidy of education for soldiers afterWW II. Accredidation standards were set up to insure that organizations that charged tuition and granted degrees and diplomas actually offered a significant education. A diploma mill, then, is an organization that awards a degree or diploma without the provision of a significant education, or without enforcing a standard of achievement by a student before conferring such an award. Basically, these organizations are willing to sell diplomas and degrees.
Sometimes the term is applied to a program within a school that is legitimately accredited. For example, some colleges and universities have been criticized for acting like "diploma mills" for some students who are star atheletes.