Cryptid
(noun) An unknown species of animal or animals which, thought to be extinct, may have survived into modern times.
Etymology
Cryptid comes from the Greek words kryptos (hidden) and ides (in sense). The word is used to denote an animal of interest to the study of cryptozoology.
A bit of history
The word “cryptid” was first coined by John E. Wall, in a letter published in a 1983 issue of International Society of Cryptozoology Newsletter (vol. 2, no. 2, p. 10). Cryptids are an unknown species of animal, or supposedly extinct animals or, sometimes, just plain misidentifications until evidence proves it one way or the other. Until proven to exist, these animals are referred to as cryptids.