Ad hoc is a Latin phrase meaning "for this". It generally signifies a solution designed for a specific problem or task, non-generalizable, and not intended to be able to be adapted to other purposes (compare a priori). Common examples are organizations, committees, and commissions created at the national or international level for a specific task. In other fields the term may refer, for example, to a military unit created under special circumstances, a tailor-made suit, a handcrafted network protocol, or a purpose-specific equation. Ad hoc can also mean makeshift solutions, shifting contexts to create new meanings, inadequate planning, or improvised events.
Ad hoc hypothesis
In science and philosophy, ad hoc means the addition of extraneous hypothesis to a theory to save it from being falsified. Ad hoc hypotheses compensate for anomalies not anticipated by the theory in its unmodified form. Scientists are often skeptical of theories that rely on frequent, unsupported adjustments to sustain them. Ad hoc hypotheses are often characteristic of pseudoscientific subjects. Ad hoc hypotheses are not necessarily incorrect. However, an interesting example of an apparently supported ad hoc hypothesis was Albert Einstein's addition of the cosmological constant to general relativity in order to allow a static universe. Although he later referred to it as his "greatest blunder", it has been found to correspond quite well to the theories of dark energy.
Ad hoc military
In military, ad hoc units are created during unpredictable situations, when the cooperation between different units is needed for fast action.
Ad hoc networking
The term ad hoc networking typically refers to a system of network elements that combine to form a network requiring little or no planning.
- Carroll, Robert T. (23 February 2012), "Ad hoc hypothesis", The Skeptic's Dictionary (John Wiley & Sons), retrieved 27 May 2013
- Texas A&M University (28 November 2007), "Einstein's Biggest Blunder? Dark Energy May Be Consistent With Cosmological Constant", Science Daily, retrieved 27 May 2013
- Howard, R. (2002), Smart Mobs: the Next Social Revolution, Perseus
- The dictionary definition of ad hoc at Wiktionary