Cryptozoology (from Greek language, kryptos, which means “hidden” + zoology, the study of animals; literally, “study of hidden animals”) refers to the search for animals whose existence has not been proven. This includes looking for living examples of animals that are considered extinct, such as living dinosaurs; animals whose existence lacks physical evidence but which appear in myths, legends, or are reported, such as Bigfoot and Chupacabra and wild animals dramatically outside their normal geographic ranges, such as phantom cats or “ABCs“.

The animals cryptozoologists study are often referred to as ”cryptids”, a term coined by John Wall in 1983.

Cryptozoology is not a recognized branch of zoology or a discipline of science. It is an example of pseudoscience because it relies heavily upon anecdotal evidence, stories and alleged sightings.

Cryptozoology has been criticized because of its reliance on anecdotal information and because some cryptozoologists do not follow the scientific method. According to Mike Dash, a Welsh historian, few scientists doubt there are thousands of unknown animals, particularly invertebrates, awaiting discovery; however, cryptozoologists are largely uninterested in researching and cataloging newly-discovered species of ants or beetles, instead focusing their efforts towards "more elusive" creatures that have often defied decades of work aimed at confirming their existence. The majority of mainstream criticism of cryptozoology is thus directed towards the search for megafauna cryptids such as Bigfoot, the Yeti, and the Loch Ness Monster, which appear often in popular culture, but for which there is little or no scientific support. Some scientists argue that megafauna cryptids are unlikely to exist undetected in great enough numbers to maintain a breeding population.  Although cryptozoology doesn’t get much respect from other scientific disciplines, it has had some spectacular success stories, including the pongo (now known as the gorilla), the okapi (an animal that looks like a cross between a giraffe and zebra), and the coelacanth (a prehistoric fish thought to be extinct).