Therianthropy is a generic term for any transformation of a human into an animal form, either as a part of mythology or as a spiritual concept. The word is derived from Greek theros, meaning "wild animal," and anthrōpos, meaning "man".
In recent time, some people have adapted the word therianthropy to describe a spiritual or psychological concept in which the individual believes they have the spirit or soul, in whole or in part, of a non-human animal, or an animal side to their nature. Such people call themselves therianthropes or therians.
The word lycanthropy has at times been used for what is more accurately therianthropy, a misconception which has led to a great deal of confusion and misunderstanding.